460 THE ANATOMY OF VSETEBUATED ANIMALS. 



The pendent jsenis of the male commonly contains a 

 bone; the testes are lodged in a more or less complete 

 scrotum ; and vesiculse seminales are generally present. 



In the female, the uterus has two long comua, and the 

 urethi'a traverses the clitoris. Sometimes there are one or 

 two pairs of teats on the abdomen, in addition to the ordi- 

 nary pectoral pair. 



The Lemuriclce are distinguishable into two families, the 

 Lemwrini and the CJieiromyini. 



In the Lemurini, the pollex is large, opposable, and almost 

 always has a broad, flat nail. 



The usual dental formula is i. z—c. — p.m. m. — , or — ;. 



22 l"!-*- 5*5 6*6 



The upper incisors are vertical, and the pairs of opposite 

 sides are generally separated by an interval. The upper 

 canines are large and pointed, and very different from the 

 incisors. The lower incisors are close set, laterally com- 

 pressed, long and procUvous, and the canines, which re- 

 semble them in form and direction, are closely applied to 

 the outer incisors. When six grinders are present, the 

 anterior three are premolars. The anterior premolars, and 

 sometimes all of them, have triangular and sharp-pointed 

 crowns ; the first premolar of the lower jaw, in fact, re- 

 sembles a canine, but its true nature is shown by its biting 

 behind the upper canine, not in front of it. 



Very generally the crowns of the upper molars are qua- 

 dricuspidate, and an oblique ridge passes from the antero- 

 external to the postero-internal cusp, as in the highest 

 Primates ; while, in the lower jaw, there are either two 

 transverse ridges, or longitudinal crescents. The cusps of 

 the molars are usually much produced, as in the Insectivora. 



In the Cheiromyini, the pollex is not truly opposable, and 

 its nail is claw-like and resembles that of the other digits. 

 All the digits of the pes, except the hallux, have compressed, 

 claw-Uke, nails. The middle digit of the manus is much 

 more slender than any of the others, and is longer than the 

 fourth. The long axis of the articular head of the mandible 

 is antero-posteiior. The dentition differs from that of all 



