THE EURYPTERIDA OF NEW YORK 245 
Eusarcus newlini (Claypole) 
Plate 36, figure 11; plates 37-39 
Eurysoma newlini Claypole. American Geologist 1890. 6: 258 
Carcinosoma newlini Claypole. Ibid. p. 400 
Carcinosoma newlini Claypole. Ibid. 1894. 13: 78 
Carcinosoma ingens Claypole. Jbid. p.77 | 
The highly bituminous dolomites of Kokomo, Ind., have afforded a 
species of Eusarcus which was described by Claypole first as Hurysoma 
then as Carcinosoma newlini. The peculiar character of this 
rock makes an unfavorable matrix and Claypole was successful only in 
outlining the body and legs of his species’ but careful treatment of a series 
of these specimens has made it possible to elucidate in some measure the 
essential structures of the creature. The type specimen has not been 
located by us (cited as belonging to Mr Newlin of Kokomo), but we have 
before us several specimens brought together by the late Professor James 
Hall and now belonging to the museum of the University of Chicago, one 
of which agrees so closely with the figure of the type as to suggest its 
identity with the latter. Another specimen [pl. 39] in the same col- 
lection, both sides of which have been preserved, excels the type in 
the distinctiveness of several important features. 
Besides these specimens we have two large individuals (one from the 
Hall collection, the other in the State museum) which correspond in size to 
Claypole’s .Carcinosoma ingens. This species was erected by 
Claypole for a specimen received from Mr Charles Smith of Akron, O. 
1 Original description. Animal measuring over all about 10 to 12 inches or even 
more in length by 4 to 5 inches in greatest breadth. The length may be allotted on 
the average thus: Head shield, 2 inches; body, 3 inches; abdomen, 4 inches: tail spine, 
2 inches; greatest breadth of body somewhat behind the middle. _ 
Of the appendages the foremost pair is the smallest with about 5 spines on each; 
the second and largest pair have at least 12, the third about 8, and the fourth about 
4 spines. From the second the appendages diminish gradually in size to the fourth. 
The large fifth pair reach only to the hind segment of the body—about 3 inches— 
and show merely the details mentioned in the general description. 
