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Show 112 MR. R. H. B U R N E O N [Feb. 19, the fingers would seem to warrant the name. Lumbricals as described by Macalister I was unable to find, and in this agree with Hyrtl. Professor Wilson ', in a critical survey of the myology of the fore-limb-called forth by an examination of the muscles of Notoryctes typhlops-notices Macalister's description of these muscles in Chlamydophorus, and expresses the belief that probably Macalister's flexor sublimis is part of the flexor profundus, a belief in which I entirely concur. He accepts Macalister's palmaris longus, and finally suggests that Macalister's short flexors are in reality the flexor sublimis still confined entirely to the hand as it is found in Ornithorhynchus and Eeptiles. This suggestion is one of great interest if well founded, but it is, I fear, not borne out by mv dissection. The two heads of the Flexor carpi ulnaris (text-fig. lo,fi.c.ul.) were far more separate than in Macalister's specimen; in tact Ihe humeral head formed an independent little muscle with an independent, though very delicate tendon inserted with that of the ulnar head on the pisiform. This muscle seems in Edentates to be liable to considerable subdivision, e. g., in Cyclothurus it consists of 4 separate bundles 2. The intrinsic muscles of the hand were not observed with sufficient accuracy to warrant any statement, except that, roughly speaking, they agreed with Macalister's description. There is a superficial muscle (palmaris brevis, text-fig. 15, pl.br.) of some size running diagonally across the palm of the hand from the base of the pisiform bone to the base of metacarpal i. This muscle does not appear to have been previously noticed. The Extensor carpi radialis (text-fig. 13, e.c.r) was inserted into the bases of metacarpals n, m by a single tendon situated exactly between them. In Macalister's specimen the tendon was double, and iu Hyrtl's single and inserted upon metacarpal n only. The Extensor carpi ulnaris (text-fig. 13, e.c.u.} had an origin from the upper part of the ulna, not mentioned by Macalister. The following muscles were also present :-Retro-clavicularis (text-fig. 14, cl.). Deltoid (text-figs. 13 & 14, dlt.). Supraspinatus. Infraspinatus (text-fig. 13, i.sp.). Teres major (text-fig. 15, t.mg.). Subscapularis(text-ti.g.~15,s.sc). Biceps (text-fig. \o,bi.). Brachialis anticus (text-fig. 13, br.a.). Supinator brevis. Extensor communis digitorum (text-fig. 13, e.c.d.). Extensor annularis (text-fig. 13, e.ann.). Extensor minimi digiti (text-fig. 13, e.d.V). Extensor ossis metacarpi pollicis (text-fig. 13, cm p.). Extensor indicis (text-fig. 13, e.i.). The Supinator longus was absent. M U S C L E S or T H E H I N D - L I M B . - Obturator externus (text-fig. 17, obt.ex.) is a well-marked triangular muscle rising from the ventral border of the obturator foramen, deep to the adductors and inserted by a round tendon upon the femur just proximal to the lesser 1 Wilson : " O n the Myology of Notoryctes typhlops:' Trans. E. Soc. South Australia, xviii. 1894, p. 44. 2 Macalister, 1. c. p. 249. |