referring to the drawings and firstly to fig1 to 5 , there is illustrated a digging point assembly 10 according to an embodiment of the invention , the point assembly 10 comprising a main point body 11 having a longitudinal axis x - x and which , in use , is connected to the working end or tip of a tyne of agricultural implement , the main body 11 carrying a pair of replaceable sub - parts comprising wear parts 12 and 13 whose purpose will become apparent further below . the main body 11 includes a blade - like base 14 having a leading end provided in this case with a transversely extending recess 15 adapted to receive a hardened tip or strip 16 ( shown in dotted outline in fig4 ) of complementary shape to the recess 15 , the tip 16 typically being formed of tungsten carbide and being secured in position by soldering . the base 14 of the main body 11 additionally includes opposite rearwardly extending side fins 17 arranged symmetrically relative to the axis x - x . the base 14 additionally may include on its underside , connector engagement means 18 for use in positively connecting the main body 10 to a tyne in a similar manner to that described in my u . s . pat . no . 6 , 401 , 834 . arranged centrally of the base 14 of main body 11 relative to the fins 17 and extending longitudinally along the axis x - x thereof is a socket member 19 ( shown also in fig6 and 7 ) which defines a hollow socket 20 which opens to the rear of the base 14 at end 21 , the socket member 19 and socket 20 tapering from the end 21 towards the leading end of the main body 11 for receipt of the tip of a tyne which is of a complementary or mating tapering shape . the socket 20 is provided with upper and lower channel portions 22 and 23 for receipt of upper and lower lugs on a tip of a tyne . the main body 11 additionally includes an upright central splitter fin 24 extending longitudinally along the axis x - x which is aligned with the socket member 19 and which extends along and forwardly of the socket member 19 . the fin 24 is inclined downwardly at its leading end 25 to meet the base 14 . the edge of the leading end 25 is formed with longitudinally extending recesses 26 to receive wear members 27 ( shown in dotted outline in fig4 ) similar to the tip 16 to protect the leading end 25 of the fin 24 against wear . a transverse opening 28 is formed in the main body 11 at the leading end of the socket member 19 ( see also fig1 ) between the socket member 19 and fin 24 and the socket 20 opens at its leading end 29 to the opening 28 . a further opening 30 is provided in the base of the main body 11 which communicates with the opening 28 as shown in fig2 , 5 and 10 to allow for the insertion of the wear parts 12 and 13 , the opening 30 being of slightly greater width than the width of the wear parts 12 and 13 . downwardly inclined shoulders 31 ( see fig1 ) are formed at the top side of the socket member 19 on opposite sides of the central fin 24 and a locator 32 for the second wear part 13 is provided at the trailing end of each shoulder 31 . the locators 32 define circular openings 33 into which ends of the second wear part 13 project in use as described further below . slots 34 are also proved in the shoulders 27 forwardly of the locators 32 . the first wear part 12 shown also in fig6 to 8 is designed to protect the leading end and sides of the socket member 19 against wear and for this purpose , the wear part 12 has a width w which is at least the width of the socket member 19 . the wear part 12 includes a bifurcated leading end 35 which is defined by a central channel or recess 36 which splits the leading end 35 of the part 12 into two spaced flanges 37 . the channel 36 is of a stepped configuration comprising an outermost part 38 which is of a width substantially the same as the width of the central fin 24 adjacent the opening 28 such that it is capable of receiving portion of the fin 24 as described below . the channel 36 also includes an innermost part 39 which is adapted to receive a retaining pin 40 ( shown in fig6 and 7 and in dotted outline in fig8 ), the retaining pin 40 having a diameter slightly less than the width of the channel part 39 but being of a greater length than the channel part 39 . the channel part 39 is also closed by an end wall 41 which closes the normal lower end of the channel part 34 whilst the operative upper end of the channel part 39 remains open so that the pin 40 can project or extend above the channel part 39 as shown in fig7 when the opposite end of the pin 40 abuts the wall 41 . a releasing hole 42 extends transversely from the channel part 49 to the outer surface of the wear part 12 to facilitate removal of the pin 40 by insertion of an appropriate pin or tool therein . the leading outer end of the wear part 12 includes at its lower end a stepped recessed portion 43 ( provided in each flange 37 ) adapted to seat on the base 14 of the main body 11 on opposite sides of the central fin 24 . transversely aligned arcuate recesses 44 are provided in each flange 37 adjacent to and above the recessed portion 43 , the recesses 44 in use being adapted to be aligned with a transverse aperture 45 in the fin 24 of the main body 11 ( see fig1 ). the first wear part 12 also includes on its rear side a rearwardly directed tongue 46 of a width slightly less than the width of the socket 20 and which is adapted to extend into the leading open end 29 of the socket 20 . the flanges 37 are concavely curved in their top surfaces to join or merge into the tongue 46 . the second wear part 13 shown in fig9 is of an elongated u - shaped configuration having a pair of opposite side arms 48 and a connecting transverse arm 49 at one end thereof adapted to be located in the opening 28 through the main body 11 , the side arms 48 being spaced apart a distance slightly greater than the width of the central fin 24 . the arms 48 are adapted to lie along the shoulders 31 on the top side of the socket member 19 on opposite sides of the central fin 24 and extend into the circular openings 33 in the end locators 32 to be captured therein . for this purposes , the arms 48 are provided with spigots 50 at their free ends which are complementary to the openings 33 and which extend beyond stops 51 adjacent the free ends . the arms 48 are additionally provided on their lower sides adjacent the stops 51 with respective rearwardly directed hooks 52 for receipt in and engagement with the slots 34 . the socket member 19 of the main body 11 is provided with a transverse opening 53 through which a retaining wire or pin may be passed and passed through a corresponding transverse opening in the tip of the tyne to positively retain the digging point 10 assembly to the tyne tip . for assembly purposes , the u - shaped wear part 13 is twisted and passed into the opening 30 from the underside of the main body 11 and then twisted back such that the respective arms 48 thereof can locate on opposite sides of the central fin 24 . the respective arms 48 are then positioned to lie along the shoulders 31 on the top of the socket member 19 on opposite sides of the fin 24 with the spigots 50 extending into the openings 33 in the end locators 32 as illustrated in fig1 with the hooks 52 being received and hooked into the slots 34 to hold the wear part 13 in position . in this position the transverse arm 49 extends transversely through the opening 28 . the other wear part 12 is then passed into the opening 30 again from the underside of the main body 11 so that the respective flanges 37 thereof locate on opposite sides of the central fin 24 adjacent the opening 28 and the tongue 46 extends into the leading open end 29 of the socket 20 . for this purpose the tongue 46 is initially inserted into the end 29 of the socket 20 and the opposite end of the wear part 12 pivoted upwardly in the direction b of fig1 . prior to pivoting the wear part 12 however , the retaining pin 40 is inserted from below in the direction c into the innermost part 39 of the channel 36 so that it projects beyond the channel 36 and abuts the end wall 41 as in fig7 . subsequent pivoting of the wear part 12 upwardly in the direction b will move the wear part 12 towards the position of fig1 , 2 and 4 . the wear part 12 is positioned such that the stepped recessed portions 43 seat on the top surface of the base 14 and the wear part 12 it can then slide forwardly on the base 14 to the position of fig1 , 2 and 4 in which the innermost part 39 of the recess 36 is closed by the fin 24 and the pin 40 is captured in the channel part 39 . in this position , the upper end of the pin 40 is located forwardly of the connecting arm 49 of the second wear part 13 and acts as a stop against the arm 49 to prevent the wear part 13 moving forwardly and detaching from the locators 32 and unlatching of the hooks 52 . as shown in fig1 , the point assembly 10 is used with a tyne 54 having a tapering tip 55 which is of a substantially complementary shape to the socket 20 . the tip 55 as shown in dotted outline in fig1 is inserted into the rear end 21 of the socket 20 and when the tip 55 is in its fully mated position in the socket 20 , the leading end 56 thereof is located adjacent to or in abutment with the trailing end of the tongue 46 of the wear part 12 which extends into the end 29 of the socket 20 . this prevents the wear part 12 being moved rearwardly from its position of fig1 , 2 and 4 in which the pin 40 prevents detachment or movement of the second wear part 13 . the tip 55 may be retained in position by a bolt or stud / nut connection as show in dotted outline between the aforementioned connector engagement means 18 on the underside of the point assembly 10 and a channel 56 on the underside of the tip 55 . tightening the bolt or nut will urge the point assembly 10 firmly into engagement with the tip 55 of the tyne 54 . alternatively the tip 55 which may have at least an apertured lug 57 may be secured relative to the point assembly 10 by means of a transverse wire 58 passed through the transverse opening 53 and lug 57 which is aligned with the opening 53 . the wear part 12 being of the same or greater width of the socket member 19 acts to protect the sides and leading end of the socket member 19 from wear when in use in soil by deflecting soil around and past the socket member 19 and the second wear part 13 protects the top shoulders 31 of the socket member 19 and also the sides of the socket member 19 by also deflecting soil away from the shoulders 31 . the wear strips or members 16 and 27 applied to the tip 15 of the digging point assembly 10 and the recesses 26 also protect leading edges of the digging point assembly 10 . typically the wear resistant parts 12 and 13 are formed of tungsten carbide or other wear resistant materials and may be readily replaced when they have excessively worn however it is usually not necessary to replace the main body 11 as it has been protected . the wear strips or members 16 and 27 applied to the tip 15 or recesses 26 are usually attached by silver soldering and therefore can also be readily replaced . for detachment of the two wear parts 12 and 13 , the tip 55 of the tyne 54 is required to be at least partly retracted from the socket 20 by release of the pin or wire 58 or loosening of the bolting connection via the connector 18 . this will permit rearward movement of the wear part 12 and detachment of the pin 50 . the wear part 12 can then be withdrawn through the opening 30 and thereafter the wear part 13 can be moved forwardly and detached . these parts 12 and 13 may then be replaced with new parts . further protection for the sides of the socket member 19 can be provided by a wire or rod 59 passed through the openings 45 which also locates in the recesses 44 in the wear part 12 and which can be bent along the sides of the wear part 12 and socket member 19 as shown in dotted outline in fig1 . the retaining wire or rod 59 passed through opening 53 and lug 57 may also be bent back on either side to further protect the sides of the socket member 19 . the main body 11 of the digging point assembly 10 may be of various designs and configurations as may be the wear parts 12 and 13 . the socket 20 defined by the socket member 19 is designed to mate with the tip 55 of the tyne 54 and therefore may be of various cross sectional forms to suit the tip 55 . the main body 11 may be varied in design to omit the slots 34 in which case the wear part 13 will be held in position by engagement with the locators 32 . alternatively the arms 48 may include opposing lugs on their inner sides which may locate in corresponding recesses in opposite side of the fin 24 or in an opening in the fin 24 . referring now to fig1 to 17 , there is illustrated a digging point assembly 60 according to a further embodiment of the invention which is similar to the embodiment of fig1 to 5 however in this case the main point body 61 is truncated at its leading end and is adapted to cooperate with a leading shroud - like wear part 62 which envelopes the leading end of the body 61 . the wear part 62 includes a leading socket member 63 which is provided with a rearwardly open socket 64 and the body 61 includes a forwardly extending stepped tongue 65 which is complementary to and adapted to be received in the socket 64 . the main point body 61 is otherwise similar to the main point body 11 of the assembly 10 including a socket 66 for engagement by the tip of a tyne or the like , a central upstanding fin 67 , opposite side fins 68 ( which in this case are also truncated ), a transverse opening 69 at the forward end of the socket 66 which opens through further opening 70 to the underside of the body 61 . the main point body 61 is also adapted to carry a pair of replaceable wear parts 71 and 73 similar to the wear parts 12 and 13 . the body 61 additionally includes a pair of side rails 73 between the leading ends of the fins 68 and tongue 65 . the leading wear part 62 additionally includes a pair of side fins or arms 74 which extend rearwardly from the socket member 63 and which in the assembled position of the digging point assembly 60 serve as extensions to the side fins 68 . the fins 74 are shaped on their underside to mate with and slide along the rails 73 . the leading end of the wear part 62 further includes upper and lower transversely extending recesses 75 and 76 adapted to receive hardened tips or strips 77 ( see fig1 and 14 ) of complementary shape to the recesses 75 and 76 . as is apparent , the recess 76 leads the recess 75 and is stepped downwardly therefrom . the tips or strips 77 are typically formed of tungsten carbide and are secured in position by soldering . the wear part 62 additionally includes on its underside and centrally relative to the fins 74 a rearwardly extending tongue 78 which extends rearwardly from the socket member 63 and terminates in an enlarged head 79 . as shown in the exploded view of fig1 , the digging point assembly 60 also includes a retaining pin 80 similar to but longer than the pin 40 shown in fig7 . the wear part 71 as shown in fig1 is as stated above similar to the wear part 12 and is designed to protect the leading end and sides of the socket 66 of the body 61 and is bifurcated at its leading end to form two flanges 81 which are adapted to be located on either side of the central fin 67 and which further form therebetween a central channel or recess 82 which is complementary in cross section to the retaining pin 80 . in this case the channel or recess 82 is open at each end . further the flanges 81 differ from the flanges 35 of the wear part 12 in that they are extended on their operative lower side beyond the channel or recess 82 to form two transversely spaced fingers or stops 83 which can extend into the opening 70 as described further below . as with the wear part 12 , the wear part 75 includes on its rear side a rearwardly directed tongue 84 of a width slightly less than the width of the socket 66 such that it can extend into the leading end thereof . the wear part 72 is of substantially the same construction as the wear part 13 of the digging point assembly 10 being of a generally elongated u - shaped configuration defined by a pair of spaced side arms 85 joined at one end by a transverse cross arm 86 . for assembly purposes , the u - shaped wear part 72 is initially located in position on the upper side of the socket 66 in the same manner as described with the wear part 13 such that the transverse arm 85 extends through the transverse opening 69 . the wear part 71 is also assembled with the body 61 in the same manner as described with the wear part 12 of the digging point assembly 10 and so that the tongue 84 extends into the leading end of socket 66 as indicated in fig1 . the retaining pin 80 is then inserted through the opening 70 on the underside of the body 61 into the channel 82 to extend above the wear part 71 as shown in fig1 it which position the upper end of the pin 80 is located forwardly of the transverse arm 86 of the wear part 72 . further in this position the two fingers 83 are located above the lower side of the main body 61 . the leading wear part 62 is then slid longitudinally onto the leading end of the body 61 . in this position , the tongue 78 is located centrally relative to the opening 70 such that when the wear part 71 is lowered , the fingers 83 are located on opposite sides of the tongue 78 and defined stops to the enlarged head 79 of the tongue 78 as best seen in fig1 . in this position , the wear part 71 prevents detachment of the leading wear part 62 from the body 61 . further in this position , the lower end of the retaining pin 80 abuts the top surface of the tongue 78 and therefore is retained in the position of fig1 . when the tapering tip 55 of a tyne is inserted into the socket 66 as shown in dotted outline in fig1 , the leading end thereof is located adjacent to or in abutment with the trailing end of the tongue 84 of the wear part 71 . this prevents the wear part 71 being moved rearwardly and upwardly from its position of fig1 . in this position , the pin 80 prevents forward movement of the second wear part 72 and it detachment from the body 61 and further the fingers 83 of the wear part 71 prevent detachment of the leading wear part 62 . as above the tip 55 may be retained in position by a bolt or stud / nut connection or by connector engagement means on the underside of the point assembly 60 . alternatively the tip 55 which may have at least an apertured lug may be secured relative to the point assembly by means of a transverse wire passed through the transverse opening in the body 61 and lug . for disassembly purposes , the tyne tip 55 is withdrawn from the socket 66 which allows the wear part 71 to be raised to retract the stop fingers 83 from opposite sides of the tongue 78 which enables the leading wear part 62 to be detached and thereafter the wear parts 71 and 72 can be removed through the opening 70 . the leading end of the fin 67 may be provided with wear strips ( as shown in fig1 and 17 and in dotted outline in fig1 ) similar to the wear strips 26 . it will also be appreciated that the shape of the various parts of the assembly 60 may be varied from that illustrated and described . it should be noted that reference to the prior art herein is not to be taken as an acknowledgement that such prior art constitutes common general knowledge in the art . the terms “ comprising ” or “ comprises ” as used throughout the specification and claims are taken to specify the presence of the stated features , integers and components referred to but not preclude the presence or addition of one or more other feature / s , integer / s , component / s or group thereof . whilst the above has been given by way of illustrative embodiment of the invention , all such variations and modifications thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as herein defined in the appended claims .