CHALICOTHEROIDEA FROM BALUCHISTAN. 



359 



forms in the greater approximation of the length and breadth, 

 being square rather than transversely elongated. 



Tlie upper figure in Plate i. represents the fourth upper 

 premolar in a sliglitl)' worn condition, and illustrates the two 

 ridges described by Pilgrim ; in the centro-internal cusp and 

 broad internal cinguliim it shows features characteristic of all 

 C h al ico th e r oi d s . 



The molars are all elongated, and in this respect ditier from 

 those of Afacrotherium, where they ai'e all square, and from Nestori- 

 therimii and Circotherimn, where the molars change from square 

 in the front one to elongate in the third. They agree best with 

 those of MoropiiSy but carry the elongation to a still greater 

 degree, and represent the greatest modification in this respect. 



The lower figure in Plate I. shows two right upper molars just 

 erupted, only the posterior half of the second being preserved. 

 The condition of this fi-agment is excellent. In shape and in 

 pattern they resemble Deperet's figures * of the milk teeth of 

 Macrotherium and also those figured by Pilgrim foi' this species t. 

 They are, however, in all probability the permanent second and 

 third molai'S, being considerably larger than the measurements of 

 the milk teeth given by Pilgrim — i. e., the third molar is 48 mm. 

 long and 36 mm. wide in the front half as against 40 mm. and 

 31 mm. The onl}" points in which these teeth differ from 

 Pilgrim's description of his specimen are that here the whole 

 external surface of the metacone — /. e., from mesostyle to 

 metastyle — is considerably smaller in the third molar than in the 

 second, and that faint ribs are present on the external surface of 

 the metacone of the second tooth and quite absent on that of the 

 third. A corresponding rib, rather more clearly marked, is 

 present on the paraeone extei-nal surface of the third molar, 

 and presumably would be found in the other molars. These ribs 

 are not shown in Deperet's figures and in Holland and Peterson's 

 figures of Af or opus they are shown only on the protocones of 

 all three molars, where, however, they appear to be strongly 

 marked. 



Text-fig. 2 shows the outline of one of the fragments of ma,ndil)le 

 which has the socket for three incisors, or the second and third 

 iiicisor and a canine — all apparently small-rooted teeth — and the 

 whole premolar-molar series except the last half of the third 

 molar. This is continued by another fragment (the dotted outline 

 in the figure) with the third and the second half of the second 

 molar. As these fragments coincide in size they may be con- 

 sidered as belonging to the same species. 



The mandible thus reconstructed shows cei-tain peculiarities. 

 Compared with tlie best-known Chalicothere {Jloropus elaUis), as 

 figured by Holland and Peteison §, it has a much flatter lower 



* Loc. cit' pi. iii. figs. 4 & 5. 



t Mem. pi. xii. fig. 3. 



X Loc. cit. 



§ Loc. cit. pi. Hi. 



