Decembek 25, 1896.] 



SCIENCE. 



935 



a; valid generic character by most authori- 

 ties. The absence of a sagittal crest in 

 Tapirus hairdii and the molariform structure 

 of the second superior premolar, a charac- 

 ter which is found in other species of Tapi- 

 rus, can hardly be considered of generic 

 value. 



The relations of the American and Euro- 

 pean species of fossil tapir have been very 

 fully discussed by Wortman * and Earle, 

 and since their paper was written I have 

 studied the original types of Protapirus oc- 

 curring in the Eocene and Oligocene of 

 France. I see no reason in changing the 

 conclusions stated by these authors. The 

 opinion f has been advanced that the fos- 

 sil tapir from the Lower Miocene of, St. 

 Gerand-le-Puy, in France, was really a 

 species of the American genus Colodon. 

 I strongly dissent from this idea, as, 

 after having examined the original type 

 of Protapirus douvillei, I can confidently 

 state that it is a true tapir and not very 

 closely related to Colodon. Again, Pro- 

 tapirus priscus of the Phosphorites belongs 

 in the same genus as the remains of the ani- 

 mal from St. Gerand-le-Puy. As the Phos- 

 phorites is ' un grand melange/ the position 

 stratigraphically of the French species of 

 Protapirus is about the same ; the Phospho- 

 rites probably including the space of time, 

 between the Upper Eocene, Gypse de Paris, 

 and the Lower Miocene or Oligocene, of St. 

 Gerand-le-Puy. As the evidence now 

 stands I can see no reason for burdening 

 paleontologioal literature with another new 

 name for the American forms of Protapirus. 



In my opinion there is ample proof to 

 show that the American genus Hyrachyus 

 occurs in the Middle Eocene of France, 

 Argenton. Monsieur Filhol % has described 

 a lower jaw with complete dentition and 



*Bull. Am. Miis. Nat. Hist., Aug., 1893. 

 tBull. Am. Mus. Nat. Hist., Dec, 1895, p. 362. 

 X M(5m. sur Lopbiodon, Mem. Soc. Geol. de France, 

 1888, Tome V. 



also isolated upper molars, which agree 

 structurally with those of the typical 

 Hyrachyus of the Bridger. 



In conclusion I do not see that Mr. 

 Hatcher brings forward any new evidence 

 to prove that the line of the true tapirs 

 was not already in the Middle Eocene, 

 Bridger, perfectly distinct from that of the 

 pseudo-tapirs. 



Osborn and Wortman have described the 

 structure of the feet in Heptodon calcicidus of 

 the Wind River Eocene, and these authors 

 have shown that in Heptodon the middle 

 metapodial was already enlarged, as com- 

 pared with the lateral metapodials, and this 

 increase in size, tending to monodactylism, 

 culminated in the genus Colodon of the 

 White Eiver Oligocene. 



The ancestral form of the true tapir from 



the Bridger is not yet clearly made out, as 



the relationship of the two species of Isecto- 



lophus to the tapir phylum is rather obscure. 



Charles Eakle. 

 New Eochelle, N. Y. 



ON TEE OCCUBBENCE OF TBOCHOSPHJEBA 

 SOLSTITIALIS IN THE ILLINOIS BIVEB. 



This interesting and remarkable rotifer 

 occurred sparingly in collections made at 

 the biological station of the University of 

 Illinois during the months of June, July 

 and August, in the summer of 1896, in the 

 Illinois E,iver at Havana, and in a perma- 

 nent marsh in the adjacent bottom-lands 

 locally known as Flag Lake. The species 

 was described by Surgeon Thorpe, E. IST., 

 from collections made in August, 1892, in 

 a pond near AVuhu, on the Yangstze-Kiang 

 River. As its specific name indicates, it 

 differs from T. cequatorialis Semper, in the 

 position of the girdle of cilia. Semper's 

 species, found in 1859 in the rice .fields of 

 the Phillipine Islands, was also rediscov- 

 ered by Thorpe in 1889 in ponds of the 

 Acclimatization Society at Brisbane, Aus- 

 tralia. Of its occurrence elsewhere nothing 



