SUBORDER B 



XENARTHRA 



99 



Family 2. Sclerocalyptidae. 



Sderocalyptus Amegh. {Hoplophorus Lund) (Fig. 122). Anterior teeth ellip- 

 tical. Carapace medium-sized, long, straight and cylindrical with anterior 

 lateral prolongation. Manus and 

 pes with four digits. Plates large, 

 with central figure very large and 

 peripheral figures small. Caudal 

 sheath composed of 5 ? anterior 

 movable rings and a long tube 

 ornamented with elliptical figures. 

 Pleistocene of Argentina and 

 Brazil. 



Lomaphorus Amegh. First anterior premolars in each jaw cylindrical. 

 Muzzle inflated. Carapace medium-sized and elongate with anterior lateral 

 prolongation. Plates with large round central figure surrounded by single 

 row of polygonal figures. Caudal sheath composed of three or four rings, 

 terminal tube short and wide. Pleistocene of Argentina. 



Pamchthus Burm. (Figs. 123, 124). First lower premolar an elongate ellipse, 

 perpendicular angles present. Manus with three, and pes with four digits. 



Fig. 122. 



Sderocalyptus lieusseri Amegh. Pampas formation, 

 Argentina. Tail from the side. i/e. (After Ameghino.) 



Panochthus tuherculatus Owen sp. Pampas formation, Argentina. Restored skeleton without shell. 



i/oo- (After Burmeister.) 



Carapace largest of order, an elongate oval with anterior lateral prolongation. 

 Dorsal region raised above pelvis in a hump. Plates marked by polygonal 

 figures of equal size and complete ; central figure sometimes present. Caudal 

 sheath with six rings and a long flattened tube ornamented with tubercles. 

 Pleistocene of Argentina. 



PalaeohoplopJiorus Amegh. Carapace medium -sized. Plates with large 

 central figure surrounded by two lines and a third incomplete line of peripheral 

 figures. Caudal sheath with 2 ? movable rings and a conical elliptical tube 

 as in Sderocalyptus. Pliocene of Argentina-. 



Brachyostracon Brown. Two anterior lower premolars elliptical, vaso- 

 dentin© ridges feebly branched ; sacrum composed of sixteen vertebrae, four 



