CACOPS ASPIDEPHOKUS 271 



it has hitherto been published. The Chelonia have, like the lizards, an 

 ectepicondylar foramen or groove. Among the Amphibia an entepicon- 

 dylar foramen was described by Cope in AcJieloma, but an examination 

 of the type specimen shows that while apparently present in one humerus, 

 in its mate there is no indication of it, and the opening in the one may 

 safely be ascribed to some accidental injury or malformation, especially 

 so since its position and form are aberrant. So, also, Euchirosaurus has 

 been restored with such a foramen, or rather with an ectepicondylar 

 opening, but quite incorrectly so. The euchirosaurian humerus is of the 

 strictly Eryops type, and like Ery ops it does not have an epicondylar 

 foramen. There are but two known amphibians, ancient or modern, with 

 an epicondylar foramen, Diplocaulus and Cochleosaurus. 



In the collections of the ITniversity of Chicago there are well preserved 

 humeri of not less than ten genera of Texas amphibians. In addition to 

 these I have examined the humeri of Acheloma and Dissorophus, and 

 Broili and Case have figured the humerus of Aspidosaurus. Of four Per- 

 mian genera the humerus is unknown — Zatrachys, Anisodexis, Cardia- 

 cephalus, and Cricotillus. The last-named genus is very doubtfully dis- 

 tinct from Crossotelos. Anisodexis is a large form, clearly allied to 

 Eryops, and doubtless with a humerus similar to that of Eryops. Cardia- 

 cephalus is a very small amphibian, altogether too small to belong with 

 any of the femora figured in plate 15. Of the remainder Cricotus may 

 possibly be represented among the unidentified forms, but pro})ably not, 

 since nearly all the material in the Chicago collections are from the 

 upper horizons, all of the humeri herewith figured, an horizon in which 

 neither Cricotus nor Zatrachys occurs. One other genus may be men- 

 tioned, Lysorophus, of which evidence of limbs is found among the 

 material in the collection, but the bones are small, almost minute. It 

 thus is almost certain that we have evidence of at least fifteen genera of 

 Permian amphibians from Oklahoma and Texas. I know of none from 

 the reputed Permian of Illinois save Diplocaulus and Cricotus. 



Of the humeri shown in plate 15 two certainly do not belong among 

 the temnospondyles, those of Crossotelos (figures 2 and 3) and Diplo- 

 caulus (figure 7). Of Crossotelos I have seen a half dozen or more 

 humeri from the Orlando bone-bed, always associated with vertebrae of 

 the typical form and never with other forms. Its character was not recog- 

 nized when first discovered, and the ends are unfortunately reversed in the 

 drawings. It is a simple bone, moderately expanded at the extremities, 

 with a rather dee]) concavity longitudinally behind, and with but a small 

 lateral rugosity. All the specimens found show an incomplete chondral 

 ossification. The form was doubtless more or less aquatic, Diplocaulus, 



