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Show 1870.] MYOLOGY OF CHAMAELEON PARSONI I. 889 Not that it could be expected, a priori, that serial muscular homologies would in it be reduced by any means to their simplest expression ; for not only is the pronation of the forearm and manus extreme, but tbe pes is also twisted in a most exceptional manner, so that the tibialis anticus is in part on the back of the leg, and so that, when the elbow and knee are placed outward in their primitive embryonic condition, the palmar surface looks mainly outward with the pollex posterior, while the plantar surface looks mainly inwards with the hallux anterior. Nevertheless the correspondence between many of the muscles is striking; and I have endeavoured to express below the various serial relationships as they have struck me-some being of course very doubtful, but others tolerably certain. The muscles outside the scapula seem to me to answer to those outside the scapula of Man, and the subscapularis of the Chameleon to his subscapularis. If this is so, the muscles arising outside the ilium I have named glutei; but Professor Rolleston* will possibly object to this. If they are the glutei, then the " ideal vertebral surface " f must be conceived to be suppressed in the Chameleon's ilium, and its external surface must correspond to the inner surface of its scapula. If they are not glutei, but serial homologues of suprascapular muscles, then the ideal preaxial surface must be deemed to have increased to the annihilation of the ideal postaxial one. On the latter hypotheses, the outside of the ilium will answer to the outside of the scapula, and there will be no glutei but the gluteus maximus-the subscapulares being thus without a homotype in the pelvic limb. The following list, as suggested by the Chameleon's muscles, is offered for inquiry :- Gluteus maximus-r-biceps. Latissimus dorsi-f flexor ulnaris. Gluteus medius and minimus. Subscapularis. Iliacus. Supra + infraspinatus + deltoid. Obturator externus-f-adductor. Coraco-brachialis. Obturator internus. Deepest part of coraco-brachialis. Extensores femoris. Triceps. Semitendinosus + semimembra- Biceps -f- brachialis anticus (?). nosus + sartorius. Ilio-peroneal. Scapular head of triceps. Gastrocnemius internus. Supinator longus. Gastrocnemius externus. Pronator teres (?). Tibialis anticus. Extensor carpi radialis longior. Extensor longus digitorum. Extensor carpi radialis brevior. Peroneus. Extensor ulnaris. Flexor longus digitorum 4- flexor Flexor longus poliicis. longus hallucis. . Flexor tertius digitorum,. Flexor longus digitorum. * L. c. p. 620. t Prof. Flower's ' Osteology,' p. 335. |