OCR Text |
Show 1875.] PLANTAR TENDONS IN BIRDS. 345 of the tarso-metatarse it is joined by the tendon of the flexor longus hallucis on its outer side, whereupon the conjoined tendon splits into three divisions to supply the three anterior toes (vide fig. 5). The peculiar conformation in the foot of the Trogonida is associated with an equally abnormal arrangement of the plantar tendons, which I have found in Trogon puella and in Pharomacrus mocinno. In these birds the tendon of the flexor longus hallucis is situated, as it •g- IV III Momotus lessoni. Trogon puella. ought to be, external to the flexor perforans digitorum ; it also crosses it superficially, opposite about the middle of the tarso-metatarse, sending down a slender vinculum in the normal manner. The peculiarity is in the ultimate destination of the tendons, the flexor longus hallucis and the flexor perforans digitorum each dividing into two near the metatarso-phalangeal articulation, the two portions of the former tendon running to the hallux and digit 2, the two of the latter to digits 3 and 4 (vide fig. 6). This arrangement is not found in any other group of birds, as far as m y experience goes. Besides the three last peculiar arrangements of the tendons, which I have not found elsewhere described, there is another still more peculiar and unexpected. I have observed it in all the Anomalo- |