American Fossil Vertebrates. — Hay. 347 
work. Hence, Dr. Leidy's original generic name adheres to the 
teeth represented by figures 35-45 of his plate and not to the 
others. On the other hand, Prof. Cope erred when he under- 
took to improve Dr. Leidy's name by writing Dinodon and 
again when, with this emendation as a basis, he accepted Au- 
blysodon. Were Deinodon Leidy and Dinodon Dumeril and 
Bibron derived from the same Greek words, Seivos and ' odoov 
it would not be necessary first to emend Deinodon to Dinodon 
to produce interference. But, while Leidy's Deinodon is un- 
doubtedly derived from the Greek words written above, Du- 
meril and Bibron's Dinodon is not so derived. If we turn to 
the famous work on reptiles by the author* just mentioned, we 
find this explanation of their generic name: "Ce nom a ete 
imagine par Bibron, d'apres I'examen de I'individu confie par 
M. Smith. II semble compose de zi/, par le milieu, de chaque 
cote, utrinque, et de Nod 005, edente." » 
This being the case, Dr. Leidy's name, in its original form 
Deinodon, is not preoccupied and is the proper name to applv 
to those species which for many years have been arranged un- 
der the generic name Aublysodon. 
It may be remarked here that more recently Prof. Copef 
has emended also the Dinodon of Dumeril and Bibron into 
Dianodon. 
The disposition of this case above detailed, which disposi- 
tion I believe to be uncontestable, on the assumption that two 
distinct genera are included in the lot of teeth described by 
Leidy, leaves those teeth represented by figures 21-34 without 
specific name. It is possible that they are covered by some of 
the specific names which have been included under Prof. 
Cope's genus Lselaps, but apparently they are not. Hence. I 
believe that I am justified in giving them a provisional specific 
title. 
The name Lselaps, having been employed in 1835 for a 
genus of Arachnida, is not available in the sense given it by 
Prof. Cope. Hence, Prof. Marsh;); properly substituted for it, 
in 1877, the name Dryptosaurus. To this genus then the teeth 
*Erp^tologie G^nerale, vol. VII, 1854, p. 447, footnote. 
tTrans. Amer. Philos., Soc, XVIII, p. 205. 
JAmer. Jour. Sci.,[3l, vol. XIV, p. 88. 
