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Show 1882.] DR. GADOW ON THE ANATOMY OF PTEROCLES. 321 M. flex, perforans et perforatus dig. il.-The strong and fleshy belly of this muscle arises with a short tendon from the hinder plane of the intercondyloid region ; it passes through a special canal in the susceptaculum, and is one of the deepest muscles. It is inserted into the cap. phal. i. dig. n. The m. flex, profundus s. communis digitorum consists of two principal heads. The outer one arises with fleshy fibres from the fibula and is partly fused with the m. tibialis ; its strong tendon passes the intertarsal joint superficially to the susceptaculum, and is only covered by the tendo Achillis ; it passes the pulley on its outer or lateral, not on its ventral or posterior margin. The inner or chief head takes its origin from the hinder plane of the greater part of the tibia ; its tendon runs as the deepest of all through the pulley, and then unites with that of the outer head; the tendon then divides into three, each of which is inserted into the basis of the last or distal phalanx of the n., in., or iv. digit. Although Pterocles possesses a rudimentary hallux, which consists of two very small bones not articulated with the metatarsus, there was no trace of a m. flexor hallucis longus to be found. But there was a m. flexor hallucis brevis, which arose from the hinder aspect of rather more than the upper two thirds of the tarso-metatarsal bone, and was inserted into the cap. phal. i. dig. i. An abductor brevis. dig. iv. and an abductor brevis dig. n. were likewise present-the former pulling the fourth toe inwards, i. e. towards, the latter drawing the second the away from the middle one. Both consequently move these two toes tibiad, and are morphologically abductors. For the m. flexor brevis dig. in. see note, § 4. Note.-Mr. Forbes has kindly drawn my attention to Mr. A. Has-well's paper " Notes on the Anatomy of Birds. III. The myological characters of the Columbida?," in Proc. Linn. Soc. N e w South Wales, 1880, p. 306 ; and has expressed grave doubts about the correctness of some of the statements made in it. Mr. Haswell, at the end of his paper, mentions five points "which seem to be especially characteristic of the family." But I find that of the five points, one is totally incorrect, and three others, viz. nos. 3, 4, 5, are not characteristic of the Columbida?. These points are:- 1. The absence of a posterior belly of the m. latissimus dorsi. Mr. Forbes and I, on examining the following birds, which were at hand-Carpophaga, Chalcophaps, and Columba-found this muscle consisting of two bellies, the posterior one being just as well developed in these Pigeons as in Astur, arising from the anterior margin of the ilium and from the last dorsal vertebra?, and inserted by means of a tendon below that of the anterior belly into the humerus. Throughout their whole length the two bellies were connected by a fascia. 3. The absence of the m. glut, externus and the presence of the adductores brevis et longus, the semitendinosus and semimembranosus. Now the in. gluteus externus (-glut, anterior) is generally very small, but plainly visible in many birds, such as Pigeons, Passerine birds, & c , and not absent as stated by Mr. Haswell. 22* |