OSTEOLOGY OF AMERICAN PERMIAN VERTEBRATES 365 



others were wholly free; such bones or parts of bones are in most 

 exquisite preservation. Doubtless had the deposit been discovered 

 sooner and the whole mass brought to the laboratory in a large 

 block, carefully bandaged, there would have been many more 

 bones recovered — bones more or less anatomically associated. 

 As it was, notwithstanding the greatest care, many bones and parts 

 of bones were lost, and others were broken, and their restoration 

 has been especially difficult, since the fragments must be adjusted 

 under a microscope, for the greater part. 



The whole collection of skeletons covered only a few square 

 feet, and probably represents a dozen individuals in various stages 

 of growth. It is not improbable that the student intent upon the 

 naming of species and genera would have described these specimens 

 as belonging not only to different species but to different genera as 

 well, had he not known the conditions under which they were 

 found. I think, however, that the remains are all conspecific, not- 

 withstanding the different sizes and degrees of growth which they 

 show. Especially do the smaller, long bones show a lack of ossi- 

 fication at the ends. I have figured parts of the skeleton of several 

 of these specimens, but have not attempted to reduce them all to 

 one scale, which could easily have been done, since the various 

 more or less articulated skeletons give the relations between the 

 different parts of the skeletons. I have made no figures, however, 

 of the bones of the young animals, save of the clavicle, which I 

 cannot find among the more adult bones. In case the future 

 "species splitter" reaches the conclusion that I have lumped several 

 allied species under one name, I may say that the larger specimens 

 of humerus and femur, originally figured, may be considered as the 

 type of both species and genus. 



One can only conjecture the reason why so many skeletons of 

 animals of one species in various stages of growth should have 

 been fossilized so closely together. Possibly a group of hibernating 

 animals were suddenly overwhelmed and drowned, or suffocated 

 and afterward covered by water. 



I may add, that in the hope of acquiring material for the 

 more complete elucidation of the form, and baffled at first in the 

 interpretation of the skull, I have delayed the full description until 



