OCR Text |
Show 1875.] PLANTAR TENDONS IN BIRDS. 341 in all attempts to identify the muscles. From these it can be inferred, as is verified by dissection, that the tendon of the flexor longus hallucis crosses its companion superficially on its way from the ankle to its insertion in the hallux. Just before, or just at the commencement of, the sole of the bird's foot (near the joint between the metatarsus and the phalanges), these two tendons generally split up to supply the toes. By far the majority of the families of birds agree in the distribution of the terminal tendons, conforming to one common type. This typical arrangement must be first described. The common Fowl (Gallus bankiva) is a very good example. The accompanying diagram (fig. 1) will Fig- I. Fig. 2. Gallus bankiva. Apteryx mantelli. assist in explaining it. The tendon of the flexor longus hallucis descending on the outer side of the tendon of the flexor perforans digitorum, crosses it superficially in its downward and inward course to the lower surface of the base of the hallux, whence it traverses the flexor surface of that digit to the base of the uugual phalanx, at which spot it is inserted. The flexor perforans digitorum continues down to the sole of the foot as a single tendon, where it immediately splits into three parts, one to the ungual phalanx of each of the three anteriorly directed digits. Opposite the lower part of the tarso- |