{HEAD ~ The undersurface} of the upper layer feed arm in {TAIL ~ the center portion} thereof is formed with an engaging face 39 and an upper layer feed dog 40 is secured to the leading end of the upper layer feed arm 38 
{ HEAD ~ The undersurface } of the upper layer feed arm in { TAIL ~ the center portion } thereof is formed with an engaging face 39 and an upper layer feed dog 40 is secured to the leading end of the upper layer feed arm 38
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH