Correspondence — Mr. R. Etheridge, Jim. 239 



not only Phenacodus and allies (=Condylarthra), but also Hyracoidea, 

 Lemuroidea, Simmopithecoidea, and Anthropoidea, although the 

 last-named diverge a little in the characters of the carpus. Moreover, 

 some of the Taxeopoda of the Puerco epoch show that the Ungui- 

 culate forms can readily have descended from them, for as the 

 carpus and tarsus of this order are thoroughly Unguiculate, it 

 only requires intermediate forms of ungues to connect tbem, and 

 these have been found. These facts and conclusions are set forth in 

 the " American Naturalist " for 1885, in a paper on the " Evolution 

 of the Vertebrata Progressive and Retrogressive." 



It thus appears that Lemurine forms were the ancestors of all 

 Placental Mammalia, as was already anticipated by Haeckel in his 

 far-seeing " Schopfungsgeschichte." E. D. Cope. 



NOTE ON ERISICHTHE. 



Sir, — A careful perusal of Mr. Davies' note on this subject in your 

 number for March reveals the fact that he agrees with me in the asso- 

 ciation of the fin-spines in question with Erisichthe, and not with 

 Ptychodus. He corrects me as to the authorship of the term Xiphias 

 Dixoni, and agrees with me again that the weapon of that species 

 also belongs to the fish I have called Erisichthe. But he wishes me 

 to use the name Protosphyrcena, Leidy, in the place of the one I 

 have proposed. In this point I hope Mr. Davies will yet again agree 

 with me. 



Two species are catalogued 1 by Leidy under the name of Proto- 

 sphyrcena, P. ferox and P. striata. If now his P. ferox be a species 

 of the genus I have named Erisichthe, Leidy's name should, in 

 accordance with all usage, be retained for the P. striata, provided 

 the two belong to different genera. When in London, in 1878, 

 either Mr. Davies or Mr. E. T. Newton showed me a jaw containing 

 teeth of the P. striata, which was plainly not an Erisichthe. For 

 this statement I depend on memory alone. If I be correct, it is for 

 this genus that the name Protosphyrcena should be retained, if it be 

 used at all. 



In its present status, however, the name in question is nomen 

 nudum, and under the rules not more entitled to recognition than 

 new names in museum or sale catalogues. The rules of the 

 American and British Associations are explicit on this point, and 

 properly so. E. D. Cope. 



NOTOCHELYS CO ST AT A, OWEN. 

 Sir, — In his description of this interesting fossil, 2 Sir Richard 

 Owen stated that the " nature and age of the deposit from which it 

 came was unknown to him." I am informed by Prof. Archibald 

 Liversidge, by whom Notochelys was sent to Prof. Owen, that it was 

 found associated with certain other fossils described 3 by myself from 



1 The name is not referred to in the text of his paper by Leidy, but only appears 

 in a catalogue at the end of it. 



2 Quart. Journ. Geol. Soc. 1882, vol. xxxviii. p. 178. 



3 Journ. K. Soc. New South Wales for 1883 [1884], vol. xvii. p. 87. 



