190].] NATURAL SCIENCES OF PHILADELPHIA. 121 



Loris, Nyctlcebus, Perodidicus and Ardocehis, aud irregularly ia 

 Microcebus^ and Galago.^ Of especial significance is the fact that 

 some of the more recenth^ described Eocene Primates^'' present both 

 a small fourth cusp and traces of the oblique ridge on the first and 

 second upper molars. In all catarrhine monkeys both upper and 

 lower molars are quadricuspid, with strong transverse ridges con- 

 necting the opposite cusps." This arrangement is not found in 

 antliropomorpha, but is shown lioth above and below in Indris,^^ 

 w hiJe Loris and Ardocebus show it in the lower jaw. 



Mr. Mivart" directs attention to the fact that in man the spinous 

 process of the third cervical vertebra is short and bifurcated ; in 

 anthropoids it is elongated and simple, while in monkeys generally 

 it is short and simple, as is the case in lemurs excepting in the 

 Ntjdicebidce., among which in Nydlcebus it is quite human, while 

 in Perodidicus and Ardocebus it is anthropoid. Similar corre- 

 spondences are exhibited by other parts of the spinal column. In 

 anthropomorpha the spinous processes of the lumbar and the last, 

 or last two, dorsal vertebra? are directed backward, the transverse 

 processes are turned slightly backward (dorsally), and the ana- 

 pophyses and metapophyses are few in number and feebly devel- 

 oped. In catarrhine monkeys the corresponding spinous processes 

 are bent forward, so as to make a distinct point of convergence 

 about the next to the last dorsal with those of the anterior verte- 

 brae, which are inclined strongly in the opposite direction; the 

 transverse processes are horizontal or more usually slightly bent 

 forward (ventrally), and the anapophyses and metapophyses are 

 strongly developed and begin usually in advance of the seventh 

 dorsal, extending posteriorly through the whole of the lumbar 

 vertebriK?. 



In all these respects lemurs agree with monkeys, excepting again 

 the Nydicebidce, where the disposition is generally as in anthro- 

 pomorpha. 



^Mivart, I c, p. 621. 



'Huxley, I. c, p. 325, fig. 5; Mivart, I. c, p. 625; Topinard, I. c, p. 

 692. 



'"H. F. Osborn, Bi/U. Am. Mus. of Nat. Hist., 1895, p. 19, fig. 4, and 

 Intt'/r national Dental Journal, July, 1895, PI. AA, fig. 10. 



" Huxley, Anat. Vert., p. 401 ; Topiuard, I. c, p. 679. 



'2 Huxley, P. Z. S., 1864, p. 326 ; Topinard, I. c, fig. 8, T. 



''P. Z. S., 1865, p. 550. 



"Mivart, P. Z. S., 1865. p. 545 et xeq. 



