MAMMALIA. 407 



molars are cylindrical, seven or eight in number throughout, separated from 

 each other, and without enamel on the inside. The tongue is smooth, and 

 but slightly extensible. Between their scales, or on those parts of the body- 

 not covered by the shell, there are few scattered hairs. They dig burrows, 

 and live partly on vegetables and partly on insects and dead bodies. They 

 all belong to the hot, or at least to the temperate parts of America. 

 Dasypus peha is found in the southern United States. They may be 

 divided into sub-genera, from considerations drawn from the structure of 

 their fore feet, and the number of their teeth. Cachicamus has four toes to 

 the anterior feet, the two middle ones of which are the longest ; only seven 

 teeth on each side, and in each jaw. The tail is long, and encircled with 

 bony rings. Dasypus noveyncinctus {pi. 112, fig. 8) is the type of this 

 section. Apara has the same toes as in Cachicamus, and nine or ten teeth 

 throughout {D. tricinctus). Encouhertus has five toes to the fore feet, the 

 three middle of which are the longest. The greater part of the tail is 

 covered with scales, arranged in quincunx. There are nine or ten teeth 

 throughout, as in Apara. D. sexcinctus {pi. 112, fig. 1) belongs to this 

 type. Cahassous has five toes to the fore feet, but directed obliquely, 

 so that the thumb and index are slender, and the latter the longest ; the 

 middle one has an enormous sharp nail : the following one has also a nail, 

 but a shorter one, and the last toe is the shortest of all. This form of the 

 foot enables these animals to divide the earth, and burrow into it with 

 rapidity, or at any rate to cling with such tenacity that it is extremely 

 difficult to tear them from it. They have but eight or nine teeth on each 

 side, and in each jaw. D. unicinctus is an example. Priodon has the toes 

 more unequal, and the nails larger than in the preceding sub-genera. 

 There are twenty-two to twenty-four small teeth throughout, or ninety-two 

 to ninety-six in all. D. gigas, the largest species of the tatous, belongs to 

 this section. It is sometimes more than three feet in length, the tail 

 included. 



Several species of the genus Dasypus are known in a fossil state, which 

 seem to indicate a wider geographical range, inasmuch as two of them are 

 said to occur in North America, D. maximus and D. antiquus. 



The genus Chlamydop/iorus has the upper part of the body covered with 

 a cuirass composed of rhomboidal plates, truncated behind, only connected 

 to the body along the spine. The rest of the body is hairy. Above and 

 below it is provided with eight cutting teeth. The fingers of the fore feel 

 are inclosed within a membrane, and provided with five strong, shovel-like 

 nails. A single species is known, Chi. truncatus {pi. 112, fig. 6), from the 

 interior of Chih, where it passes the most of its time under the ground. 



The extinct genera of this family, among which are some gigantic forms, 

 are not without afl[inities with Bradipodidee, which they connect more inti- 

 mately with Dasypodidae, so distant from each other when the living types 

 alone are taken into consideration. The genus Glyptodon has the charac- 

 teristic descending zygomatic apophysis of the Megatheridae ; but the feel 

 are bulky, and the phalanges, to which nails articulate, are short and 

 depressed. The molars, eight above and eight below, come nearer those 



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