13 DESCRIPTIONS OF PREPARATIONS. 



the nasal, constituting ' naso-turbinal ' bones ; the loose often lost attach- 

 ment of the much convoluted inferior turbinals to the maxillaries l ; in the 

 formation by the posteriorly expanded vomer of a floor to the true olfactory 

 portion and of a roof to the lower narial or respiratory portion of the nasal 

 cavity ; in the wide interval between the pterygoids and the tympanic bulla, 

 and in the presence in this last bone of a canalis caroticus. The pitted 

 appearance of the interparietal bone, of the upper part of the occipital bone 

 in apposition or fused with the interparietal, and of the upper arch of the 

 first cervical vertebra, is worthy of note as suggesting a comparison with 

 Lophiomys, and with the rugose 2 zygomatic and frontal bones in the Paca 

 (Coelogenys pacd}. In aged specimens this pitting almost amounts to fene- 

 stration. The anchylosed tibia and fibula are specially noteworthy. 



The imperfection of the clavicles in the Rabbit and Hare prepares us 

 for their entire absence as reported to exist in some few of the Subungulate 

 Hystricomorphi, and contrasts with their complete development in some 

 families of the same suborder (Chinchilloides, Spalacopodoides), as also in the 

 entire suborders Myomorphi less Lophiomys, and Sciuromorphi, and even in 

 the subgenus of the suborder Lagomorphi represented by the tail-less Hares, 

 Lagomys. The presence of a backwardly and downwardly projecting pro- 

 cess of the acromion is similarly a peculiarity observable in the Lagomorphi 

 and certain Hystricomorphi, whilst it is absent in many Rodents, though 

 present in other orders of Mammalia, and notably in the Elephant. 



The non-development of fangs confers the same privilege of perpetual 

 growth on the molars of the Lagomorphi, the true Cavies, and the Chinchillas, 

 which is enjoyed by the incisors of all Rodents. The white colour and the 

 shortness of the incisors again are points of similarity between the Hares 

 and the Cavies. The number of molar teeth is greater in the Hare and 

 Rabbit than in any other Rodents, being f as against -f in the allied sub- 

 family Lagomys, against in Hystricomorphi and Sciuromorphi, in Myo- 

 morphi, and f in Hydromys. The vacuity in the lower jaw, posteriorly to 

 the socket for the last molar tooth, and the vertical upgrowths from the 

 tubercles of the second to the eighth pair of ribs, are peculiarities in the 

 skeleton of the Lagomorphi. 



In the ossa ilii the glutaeal surfaces are much more extensive than the 

 iliac, a line drawn forwards from the tubercle for the short head of the 



1 The maxillo-turbinals are more complexly and finely convoluted in the Rabbit than in the 

 Hare, the subterranean habits of the former of these animals creating a greater need for warming the 

 inspired air. Similarly, as remarked by Professor Flower (Osteology of Mammalia, p. 183, second 

 edition, 1876), in the Elephant, where the inspired air is sufficiently warmed by having to pass along 

 the elongated proboscis, the maxillo-turbinals are wholly aborted. 



2 See Flower Osteology, p. 156; and Waterhouse, History of Mammalia, ii. p. 369, who 

 suggests that periodical deposition analogous to that of the horns of deer causes this. Compare the 

 strange account of Lepores cornuti given by Schreber, Saugethiere, i. Taf. cclxxxiii. B; Pallas, Novae 

 species Glirium, p. 14, ibique citata. 



