PROSIMIAE. 649 



the cardiac end of the stomach produced into a long narrow caecum. 

 They are fimall bats and suck the blood of men, horses and cattle 

 and probably of other warm-blooded animals. 



Order 21. Prosimiae.* (Lemuroidea). 



Plantigrade, usually pentadactyle, arboreal animals with oppos- 

 able pollex and hallux. The orbit is closed behind by a bar of bone 

 formed by the union of the frontal and jugal, but is not completely 

 shut off from the temporal fossa by a wall. Digit No. 2 of the pes 

 always has a claw. 



The lemurs are small or medium -sized, for the most part 

 nocturnal animals, covered with fur and usually provided with 

 a long tail which is never prehensile. They are generally quad- 

 ripedal, and the pollex and hallux are always well developed 

 and opposable. 



The dentition varies in the different families so that no general 

 formula can be given for it, but except in Chiromys, which has 

 no canines, all kinds of teeth are present. In living species it 

 is usually i f c \ p lH^ m ^, but in some of the extinct 

 forms attributed to this group from the Eocene and L. Miocene 

 it is i fori c \ p ^ m ^, the teeth extending without a 

 break along the jaw. The molars are tri-or quadri-tubercular, 

 and the cusps are connected by low ridges. The third lower 

 molar usually has a small talon. The premolars are always 

 simpler than the molars, and have one sharp cusp, but the last 

 may be molar-like. 



The brain case is small relatively to the size of the face, which 

 is generally elongated. The orbits, though completed behind 

 by the bony union of the jugal and frontal are not completely 

 shut off from the temporal fossa as in apes, nor does the lateral 

 plate of the ethmoid enter into the inner wall of the orbit but 

 is shut off by the maxilla. The lacrymal foramen is on the 



* Mivart, Crania and Dentition of Lemuridae, P.Z.S., 1864 and 1867. 

 Mivart and Murie, Anatomy of Lemuroidea, Trana. Zool. Soc, 7, 1872. 

 Turner, Placentation of Lemurs, Phil. Trans., 166. A. Milne-Edwards, 

 L'embryol. d. Lomuriens et les affinites de oee animaux. Ami. Sci.Nat., 

 1871, and Classification des Lemurieus, Revue Scientifique, 1871. A. 

 Milne-Edwards and Grandidier, Hist. Nat. de Madagascar, Mammiferes, 

 I and 2, 1875-96. Winge, Primates, E. Miiseo Lundii, 1895. Schlosser, 

 op. cit., see under Carnivora. Wortman, Studies of Eocene Mammalia 

 in the Marsh Collection, American Journal of Science, 15, 1903, pp. 163, 

 399, 419. Hubrecht, The Descent of the Primates, New York, 1897. 



