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Show 292 MESSRS. B. C. A. WINDLE AND F. O. PARSONS ON [Nov. 3, 16. Almost constant absence of peroneus brevis. 17. Absence of accessorius pedis. 18. Constant presence of trachelo-mastoid. 19. Absence of pyramidalis. We will next consider whether the division of Subungulata (comprising the Hyrax and Elephant) has any special points distinguishing it from the Ungulata vera. Myological Characteristics of Subungulata. 1. Semimembranosus and presemimembranosus have ischial and caudal heads, but these are also found in the Perissodactyla. 2. Sartorius always absent in Hyrax and often in Elephant. 3. Tibialis anticus has no femoral origin, 4. Lumbricales are fairly well developed, but so they are in the Tapir. 5. Abdomino-humeralis well developed. 6. Palmaris longus present. 7. Flexor brevis digitorum manus present. It will be seen, therefore, that there are not many points common to the Hyrax and Elephant, but nos. 3 and 7 are certainly significant so far as they go. Between the Artio- and Perissodactyla there are a good many rather striking points of difference. Myological Characteristics of the Artiodactyla. 1. Ectogluteus is inserted into the fascia of the thigh. 2. Obturator internus rises outside the pelvis. 3. Obturator tertius (so-called) is present. 4. Semi- and presemimembranosus have only an ischial head. 5. Semitendinosus has usually only an ischial head. 6. Lumbricales are absent except in the Hippopotamus. 7. Splenius colli is feeble or absent. Myological Characteristics of the Perissodactyla. 1. Ectogluteus is inserted into the third trochanter. 2. Obturator internus rises inside the pelvis. 3. Obturator tertius absent. 4. Semi- and presemimembranosus have ischial and caudal heads, 5, Semitendinosus has ischial and caudal heads. 6. Lumbricales usually present. 7. Splenius colli strongly developed, Speaking, therefore, from a myological point of view, there is good reason for dividing the Ungulata vera into two sharply defined groups, but there is little reason for placing the Hyrax and Elephant together in a separate division, for, excepting the absence of the femoral origin of the tibialis anticus and the |