SYSTEMATIC REVISION 57 



directed forwards and a little laterally; they are separated by a space equal 

 to the transverse diameter of each. The auricular meatus is large and is 

 directed outwards and not upwards. The posterior hooks of the quadrate 

 project on each side beyond the slightly concave posterior border of the 

 cranial table. Interorbital region flat, consid- 

 erably wider than the diameter of the orbit. 



"The carapace commences at a point ^ . 



about as far posterior to the skull as the y^^"^^^ ''•'s^^^ 



posterior border of the latter is behind the ^^^ ^^^Z ^^^ 



orbits. The anterior band has an obtuse (—- 



anterior border like that of the anterior bor- I ^ 



der of the carapace of an armadillo. The ^— 



bands are gently convex from side to side, ^'°- ^o.—Dissorophus (Otoeaius) mimeticus. 



and they become narrower anteroposteriorly ^^ixniL!^ci^:iori^L^'''''' "' 



as we pass backwards. The state of the 



specimen is such that neither ribs nor vertebrae can be discovered. 



"As compared with 0. testudineus the following differences appear: The 

 table of the skull projects beyond the posterior hook of the quadrate in the 

 former; not so far in the latter. The auricular meatus and orbit present 

 more laterally in the 0. mimeticus, more vertically in the 0. testudineus. 

 The size of the two species is not very different. 



"Measurements. mm 



"Length of the skull on middle line I20 



Width of the skull at posterior border of the orbits 90 



Width of the skull between the orbits 38 



Width of the skull between the nostrils 22 



Length of the skull (median) to anterior border of orbits 78 



Distance from skull to carapace. 66 



Length of thirteen carapacial bands 155 



Anteroposterior diameter of first band 17 



Anteroposterior diameter of seventh band 12 



"The species is named to indicate the superficial resemblance to Dis- 

 sorhophus." 



Revised description: There is only one recognizable species, D. multi- 

 cinctus; the revised description is contained in that of the genus. 



Following are the original descriptions of the family Otoccelidce and the 

 species Otoccelus mimeticus and 0. testudineus. They are inserted to show 

 Cope's ideas as to their position and relationship. 



Family OTOCCELID^ Cope. 

 Am. Nat., vol. xxx, 1896, p. 398; Proc. Am. Phil. Soc, vol. xxxv, 1896, p. 122. 



Original description: " Cranial roof excavated laterally behind, forming 

 a large meatus auditorius. Teeth present, in a single row, not transversely 

 expanded. Ribs overlain immediately by parallel, transverse dermoossi- 

 fications, which form a carapace." 



In the "Proceedings of the American Philosophical Society" he gave 

 a much more extended description of the family: 



"Posterior border of the roof excavated laterally by the meatus audi- 

 torius externus. Teeth present in a single row, not transversely expanded. 

 Ribs immediately overlaid by parallel transverse dermoossifications which 

 form a carapace. 



