92 E. H. Barbour — New Longirostral Mastodon. 



slightly decurved, is 5^ feet (l,678 mm ) in length, and 4J inches 

 (114 mm ) in diameter. Unlike Eubelodon morrilli, the tnskhas 

 an enamel band, although narrow and almost vestigial, and the 

 tip is worn to a very obtuse wedge. The two associated 

 humeri seem uncommonly short and stout. They are scarcely 

 more than 30 inches (763 mm ) in length. It seems worthy of 

 notice that, in the case of the Brown County mastodons, the 

 acetabula have bold, cotyloid notches, and singularly deep, 

 broad cotyloid fossae, which are roughened and deeply pitted. 

 This indicates that the round ligaments were present, that they 

 were uncommonly large. The heads of the femora show 

 unmistakable scars. With so many examples at hand, it seems 

 beyond the limit of probability that this is coincidence. Con- 

 trary to the usual rule, all of these mastodons seem to have 

 had the ligamentum teres strongly developed. In the case of 

 the acetabula of Tetrahelodon lulli, the fossae are narrow and 

 deep, and the heads of the femora have corresponding scars. 

 In Elephas, the acetabular fossae are nearly obliterated, and the 

 heads of the femora are without scars. Absence of this liga- 

 ment has been counted a character of the Proboscidea, but 

 the Brown and Cherry County mastodons seem to be excep- 

 tions to the rule. 



The following associated fossils have been noted : Testudo- 

 orthopygia, Testudo indet., Alticamelus, Camel indet., Para- 

 hippus, Hipparion, Neohipparion, Teleoeei^os fossiger, and 

 Merycodus neoatus. 



In the Nebraska State Museum, the following proboscideans 

 from Nebraska are represented : Tetrahelodon lulli, Tetrahelo- 

 don willistoni, Eubelodon morrilli, Tetrahelodon eu/iypodon, 

 Mastodon merificus, Mastodon americanus, Elephas eolumbi, 

 Elephas imperator, Elephas primigenius, and several undeter- 

 mined forms believed to be distinct. 



The University of Nebraska, 



Lincoln, September 15, 1914. 



