ANTHROPOIDEA 699 



and the first upper incisor are enlarged, the upper molars 

 (Fig. 334) tri tubercular, and the lower quadritubercular. Indrodon, 

 of the lowest Eocene of the United States, resembles Plesiadapix in 

 its tritubercular upper molars, and appears to have a nearly similar 

 dental formula. Mixodectes, of the same deposits, was probably a 

 more or less closely allied type. Pelycodus of the Wasatch Eocene 

 of North America, in which the hallux was not opposable, and 

 Cryptopithecus of the German Eocene, may be regarded as very 

 generalised Lemuroids. 



Bibliography. Besides the works and memoirs on particular families and genera 

 referred to above, see St. G. Mivart, "Notes on the Crania and Dentition of 

 the Lcmuridce" in Proc. Zool. Soc. 1864 (pp. 611-648) and 1867 (pp. 960-975) ; 

 Mivart and Murie, "On the Anatomy of the Lemuroidea," in Trans. Zool. Soc. 

 1872, vol. vii. pp. 1-113 ; W. Turner, "On the Placentation of the Lemurs," iu 

 Phil. Trans, vol. clxvi. pp. 569-587 ; F. Pollen and D. C. Van Dam, Recherckes 

 sur la Faune de Madagascar, 2 me parte, " Mammiferes," 1868. For the fossil 

 types see M. Schlosser, "Die Affen., Lemuren, etc., des Europaischen Tertiars," 

 in Beitr. Pal. (Estr-Ungar, 1888. 



ANTHROPOIDEA. 



This suborder includes the whole of the remaining members of 

 the Primates, namely, those animals commonly known as Marmosets, 

 Monkeys, Baboons, and Apes, together with Man himself. The 

 characters by which the Anthropoidea are distinguished as a whole 

 from the Lemuroidea may be summarised as follows. Skull with 

 the orbit separated from the temporal fossa by a vertical plate of 

 bone joining the postorbital bar, and the lachrymal foramen situated 

 within the margin of the orbit. Pollex sometimes rudimentary or 

 absent ; second digit of manus always well developed, and that of 

 the pes usually with a flattened nail (not so in Hapalidce). The 

 cerebral hemispheres of the brain either completely or almost 

 completely cover the cerebellum, and are much convoluted. 

 Uterus not bicornuate. The placenta is deciduate and discoidal ; 

 and the allantois is small. There are never abdominal mammae. As 

 additional points of distinction from the Lemuroidea, it may be 

 mentioned that the anterior cornu of the hyoid is shorter than the 

 posterior; the inner pair of upper incisors are in contact in the 

 middle line ; and the transverse portion of the colon extends unin- 

 terruptedly across the abdomen. 



The Anthropoidea may be divided into the five families Hapa- 

 lidce, Cebidce, Cercopithecidce, Simiidce, and Hominidce, of which the 

 first and second are confined to the New, and the third and fourth 

 to the Old World. 



In noticing some of the salient features in the external and 

 internal structure of the Anthropoidea it will be found convenient 



