486 DR. C. I, FORSYTH MAJOR ON 



Tlie only known palate of Titanomys is that figured by Pilliol *, which too is elongate. 

 According to him t, the length of the palatal bridge in Lacjomys and Titanomys 

 respectively is as follows : — 



millim. 



Lagomys tibetanus ()'002. 



Lagomijs oyoloita 0"0015. 



Titanoimjs rismovieiisis. . . 0'0045. 



The suture between the palatines and maxillaries is not shown in the iigure of 

 Titanomys. Thanks to the kindness of Mons. M. Boule, I have been able to examine the 

 original in the Paris Museum, and can state that in this oldest member of the Lagomyidse 

 the family character is already very evident in the reduction of the maxillaries, 

 inasmuch as the palatines occupy the anterior margin of the bridge in the middle line, the 

 two maxillaries not joining each other. The difference in the length of the palatal bridge 

 between Titanomys on the one side, and Lagomys (with Prolagns) on the other, is tlierefore 

 wholly due to the greater elongation of the former's palatine. lu Falceolagus 1 both 

 bones are lengthened, as compared with other Leporidae, and especially with the most 

 modernized species of tlie family . The anterior palatal notch formed by the maxillaries 

 extends forward slightly beyond the anterior margin of p. 3, as it does in Nesolagus 

 Netscheri (PI. 39. fig. 38), which is one of the most primitive of recent Leporidse. The 

 posterior palatal notch of Pala;olagus reaches as far backward as a line uniting the 

 middle of the alveoli of m. 1. Besides, the horizontal portion of the ossa palatiua is also 

 transversally much less reduced than in most of the recent Leporidaj, the breadth of the 

 posterior palatal notch being approximately equal to half the breadth of the space 

 between it and the alveoli. While in this latter character JPalceolagus convei'ges 

 towards the Lagomyidse, or rather goes beyond them — for, to judge from the figiires, the 

 palatal notch of Palceolagus is considerably narrower tlian even in Titanomys — it is 

 thoroughly leporine with regard to the part which the maxillaries take in the formation 

 of the bony palate. 



Those among recent Leporidse which, on account of their several primitive characters, 

 may be placed in a separate section (Caj)rolagus-group), as oj)posed to Lepus s. str., are 

 more primitive also in the character of the greater autero-posterior length of the palatal 

 plates of the palatine and maxillary bones, as may be judged from various instances 

 figured in PI. 39. Pig. 32 represents the palate of Cajjrolagusjiisjjidus (Pears.) ; fig. 33, of 

 Sylvilagiis {Romerolagus) Nclsoni; fig. 37, the same part of Oryctolagus crassicaudatus 

 (Geoffr.) i fig. 38 that, already mentioned, of Nesolagus Netscheri of Sumatra. It is well 

 known that the bony palate of the Rabbit, of which a figiu'e is not given here §, has a 

 greater longitudinal extension than ia the Common Hare and that its palatal notch 

 is narrower ; both these characters are much more pronounced in the young. Pig. 35 



* H. Filhol, " Etude des Mammiferes fossiles de Saint-Gerand-le-Puy (AUier)," Ann. Sc. Gcol. x, pi. 3, lig. 13 

 (1879). t 0^>. cii. p. 31. 



+ Cope, ap. cit. pi. Ixvi. figs. 1, 4. 



§ lixoeUent lower views of skuUs of the Rabbit, side by side with those of Lepus ewopceus, have been figured by 

 H. V. Nathusius (' Uber die sogenannteu Leporiden," pi. ii. 187G). 



