12 MEMOIR ON THE III. 



to the Jefferson collection deposited by the American Philosophical Society in the 

 cabinet of the Academy. 



The specimen is rather too small to determine positively whether it is a distinct 

 species or not from Bison latifrom. It did not belong to an aged individual, as the 

 suture is still open between the frontal bone and that portion of the parietal which 

 forms the upper boundary of the temporal fossa. It belonged to a species of Bison, 

 as indicated by the advanced position of the horn-core, and resembles more the 

 corresponding part in the Bison priscw of Europe, as represented by Cuvier and 

 others, than it does that of Bison latifrow. The horn-core is more abruptly 

 conoidal, and relatively more curved than in the latter. It is not improbable, 

 however, that the fragment may have belonged to a female of Bison latifrons. The 

 only characteristic measurements to be obtained from it are as follow : 



Length of the fragment of horn-core . . . . 10 inches. 

 Circumference on a line with the basal margin inferiorly 14 J " 



do. five inches from the basal margin superiorly 10 " 



COO IBI I 1C 1 1 ?! LKIDY. 



This is a new genus proposed in the Proceedings of the Academy of Natural 

 Sciences, upon two species of extinct ox of North America. Its diagnostic charac- 

 ters, so far as they have been ascertained, are distinct, and briefly as follow : 



1. The os frontis rises into a hump, or forms a prominent process, from the sides 

 of which arise the horn-cores. 



2. The latter arise above and posterior to the orbits, but considerably in advance 

 of the inion, and curve downwards in their course, but do not turn up at the tips, 

 as in Ovibos. 



3. The species possess lachrymal depressions, or larmiers, as well developed as 

 in cervine animals. 



Bootherium is closely allied to the Musk Ox, Ovibos moscJiatus, Blainv. ; and pro- 

 bably, like the latter, the species were clothed in a long fleece, and inhabited the 

 great valley of the Mississippi, just anterior to the drift period. The genus occu- 

 pies a position intermediate to Bos and Oois. 



BOOTHERIUM CAVIFRONS, LEIDY. 



Bos Pallasii, DE KAY: An. Lye. Nat. Hist, of New York, Vol. II. p. 280, PI. VI.; New York Fauna, Pt. I., 

 Zool. p. 110; COOPER: Araer. Month. Journ. of Geology, Vol. I. p. 173; HARLAN : Med. and Phys. Re- 

 searches, p. 276; Edinb. New Phil. Journ. XVII. 359; H. T. METER: Nov. Act. Acad. Nat. Cur. "xVII. 

 1835, p. 155; GIEBEL: Fauna d. Vorwelt, I. p. 154. 



Bos bombifrons : Proc. Am. Assoc. Cincinnati, 1851, pp. 179, 235. 



Bootherium cavifrons, LEIDT : Proc. Acad. Nat. Sci. Vol. VI. p. 71. 



Through the kind recommendations of several friends, Professors Baird and 

 Agassiz, and Mr. W. S. Vaux, Mr. Thomas Kite, of Cincinnati, Ohio, brought 

 with him to Philadelphia for my inspection, in the spring of 1852, an excellent 

 specimen of the cranium proper of an extinct species of ox, to which I have given 



