SKELETON OF WILD RABBIT. 9 



microscopic character of the molar enamel of all Rodents (except Leporidae and 

 Hystriddae) to that of the Proboscideans, see Trans. Odont. Soc. vol. iii. p. 239, 

 1871. 



For the classificatory value of the ossicula auditus, see A. Doran, Tr. L. S. 

 1878, p. 418. 



For other characters of the order Rodentia, see Waterhouse, Natural History of 

 the Mammalia, vol. ii. pp. 1-9, 1848; De Quatrefages, Considerations sur les 

 caracteres zoologiques des Rongeurs, Paris, 1840 ; Milne-Edwards, Recherches sur 

 les Mammiferes, i. 1868, pp. 29, 30. 



For those of the Myomorphi, see Osteological Catalogue, Royal College of 

 Surgeons, vol. ii. Preparations 2223-2245 ; Waterhouse, Mag. Nat. Hist., /. c. p. 

 92; Brandt, /. c. pp. 152, 156, 300; Peters, Monatsber. Ak. Berlin, 1867. 



For the Carpus and Tarsus and Shoulder-girdle, see Gegenbaur's Untersuch- 

 ungen zur Vergleichenden Anatomie, Hft. i. ii. 1864, J 865 ; for the shoulder-girdle 

 and sternum, see also Gotte, A. M. A. xiv. 1877 ; Ruge, M. J. vi. 1880; Hoffman, 

 Niederland. Archiv fur Zool. v. 1879-82. For the carpus, see Leboucq, Arch, de 

 Bidl. v. 1884; carpus and tarsus, Baur, Z. A. viii. 1885. 



For the ' Canalis Temporalis,' or ' Foramen jugulare spurium,' see Otto, Nova 

 Acta, xiii. pt. i. p. 27; Luschka, Dk. Wien. Akad. xx. 1862, p. 204; and Kolliker, 

 Entwickelungsgeschichte, p. 929, 1879. 



For th$ means whereby the vertebral centra are articulated in the different 

 classes of vertebrata, see Rathke, Entwickelungsgeschichte der Wirbelthiere, mit 

 einem Vorwort von A. Kolliker, 1861, p. 130. 



3. SKELETON OF WILD RABBIT (Lepus cuniculus, vzr.fera). 



THE skeleton of the Rabbit differs from that of the Rat and many 

 though not all other Glires Myomorphi, not merely in such points as its 

 larger absolute size, the incompleteness 1 of its clavicles, the absence save in 

 rudiment of a hallux, the unguiculate character of its pollex, the number 

 and rootlessness of its molars, and the smaller number of its caudal verte- 

 brae, but in many points of greater morphological importance than any of 

 these. Some of these latter points show that the suborder Lagomorphi is 

 more closely allied than the Myomorphi to certain lower forms of Verte- 

 brata ; others indicate more clearly than is seen in the Myomorphi that a 

 certain affinity exists between the Rodentia s. Glires and the large Ungu- 



1 The older zoologists (e.g. Fischer, Synopsis Mammalium, 1829, pp. 286, 366; Catalogue 

 of the Royal College of Surgeons, Part iii. 1831, pp. 79, 87) divided the order into the two sections 

 of Glires daviculis completis, saepe validissi?nis, and Glires claviculis nullis aut imperfectis. The 

 inadequacy of this basis of classification may be judged of by the fact that the tail-less Hares 

 (Lagomyes\ which form a subfamily, as shown by Pallas, Glires, p. 28, closely allied to the true 

 Hares, have complete clavicles. In the Rabbit no trace of the clavicle is visible at birth (see Parker, 

 Shoulder-Girdle, PL xxv. Figs, i, 2, pp. 207-210 ; Flower, Osteology of Mammalia, p. 229), 

 though it becomes developed before adult life. In the human subject, on the other hand, the clavicle 

 ossifies before any other bone in the developing foetus. 



