31 



bristled with cusps, and are associated with canines and 

 incisors : they are unguiculate, plantigrade, and pentadactyle, 

 and they have complete clavicles. Like Rodents, they are 

 temporary testiconda, and have large prostatic and vesicular 

 glands : like most other Lissencephala, the Insectivora have 

 a discoid or cup-shaped placenta. They do not exist in 

 South America and Australia ; their office in these continents 

 is fulfilled by Marsupialia; but true Insectivora abound in 

 all the other continents and their contiguous islands. 



The order CHEIROPTERA, with the exception of the modi- 

 fication of their digits for supporting the large webs that serve 

 as wings, repeat the chief characters of the Insectivora: a 

 few, however, of the larger species are frugivorous and have 

 corresponding modifications of the teeth and stomach. The 

 mammas are pectoral in position. 



The most remarkable examples of periodically torpid 

 Mammals are to be found in the terrestrial and volant Insecti- 

 vora. The frugivorous Bats differ much in dentition from the 

 true Cheiroptera, and would seem to conduct through the 

 Colugos or Flying Lemurs, directly to the Quadrumanous 

 order. The Cheiroptera are cosmopolitan. 



The order BRUTA, called Edentata by Cuvier, includes 

 two genera (Myrmecophaga and Manis) which are devoid of 

 teeth ; the rest possess those organs, which, however, have no 

 true enamel, are never displaced by a second series, and are 

 very rarely implanted in the premaxillary bones. All the 

 species have very long and strong claws. The ischium as well 

 as the ilium unites with the sacrum ; the orbit is not divided 

 from the temporal fossa. The Three-toed Sloths (Brady- 

 pus) manifest their affinity to the oviparous Yertebrata by the 

 supernumerary cervical vertebras supporting false ribs and by 

 the convolution of the wind-pipe in the thorax ; and I may 

 add that the unusual number three and twenty pairs of 

 ribs, forming a very long dorsal, with a short lumbar, region 

 of the spine, in the Two-toed Sloth (Cholcepus), recalls a 

 lacertine structure. The same tendency to an inferior type 



