126 EDENTATA. 



43241. The loft femur ; from Buenos Ayres. This specimen agrees 

 precisely "with the one figured by Burmeister in the ' An. 

 Mus. Buenos Aires,' vol. ii. pi. viii. ; the characteristic 

 deep pit on the anterior surface above the trochlea is well 

 shown. Presented by Sehor L. J. Fontanel, 1871. 



19947 a. The right fourth metatarsal ; from Buenos Ayres. This 

 specimen agrees precisely with the corresponding bone of 

 the foot figured by Burmeister, op. cit. pi. x. fig. 1 ; the 

 metapodials of the present genus are readily distinguished 

 from those of Glyptodon by their more elongated form. 



Purchased, 1846. 



Genus HOPLOPHORUS, Lund \ 



The carapace is usually thin and composed of articulated quad- 

 rangular or pentagonal scutes, in which the sculpture generally 

 consists either of a rosette composed of a large central disk, with 

 eight or more smaller peripheral disks separated by shallow grooves, 

 or simply of a central disk surrounded by radiations ; the surface of 

 the disks being comparatively smooth. The anterior lateral scutes, 

 at least in some species, are elongated antero -posteriorly and of 

 oblong shape. The peripheral scutes of the carapace, at least in 

 many species, are not elevated into conical protuberances, but its 

 antero-inferior angles are produced in advance of the nuchal border. 

 The caudal sheath has several movable rings, and terminates in a 

 long conical tube, ornamented with a number of large disks, sur- 

 rounded by a series of much smaller ones ; in the lateral region 

 of the extremity some of the disks become of very large size. 

 The fronto-nasal region of the cranium is somewhat less convex 

 than in Panochthus ; the humerus has an entepicondylar foramen ; 

 and there are four perfect digits in each foot ^ The majority of the 

 species are of moderate size, but certain specimens provisionally 

 referred to the genus indicate a very large form. The genus 

 comes nearer to the Pasypodidce than any other member of the 

 family, as is shown by the elongated form of the carapace, its 

 produced antero-inferior angles, and the presence of an entepi- 

 condylar foramen to the humerus. 



^ Ann. Sci. Nat. s6r. 2, yoI. xi. p. 217 (1839). The name also occurs in the 

 Overs. K. Danske Vid. Selsk. Forhandl. 1838, p. 11. The real authority for 

 the name must, however, be taken later, as the type species (H. ctiphractus) 

 has been shovpn to belong to Glyptodon. 



These characters have been verified only in some of the species. 



