Bird feet and legs only a small extension of the cnemial crest. In grebes both a normal patella and an extension of the cnemial crest are found. The fibula is reduced and adheres extensively to the tibia, usually reaching two-thirds of its length. Only penguins have full-length fibulae. The bird knee joint between the femur and tibia (or rather tibiotarsus) points forwards, but is hidden within the feathers. The backward-pointing "heel" (ankle) that is easily visible is a joint between the tibiotarsus and tarsometatarsus. The joint inside the tarsus occurs also in some reptiles. It is worth noting here that the name "thick knee"
Tibia fusus cm (9 in.). These shells are large, spindle-shaped with moderately convex turns and an extremely long, thin and slightly curved siphonal canal. The basic color ranges from straw yellow to reddish-beige. The aperture is ovate and white inside, with 6 fingerlike growths on the outer lip. It is a fairly common species where it occurs, but because of its attractive appearance, it is highly sought after by shell collectors. Embryos develop into free-swimming planktonic marine larvae (trocophore) and later into juvenile veligers. Tibia fusus Tibia fusus, common name Spindle tibia or Shinbone Tibia Gastropod, is a species of large sea