330 Annals ok the Carnegie Museum. 



done for the writer's personal collection, while other parts of the ma- 

 terial were obtained for the Cornell and Carnegie Museums. I am 

 greatly indebted to Professor Ceorge H. Hudson, of the Plattsburgh 

 Normal School, and to Professor Cilbert I). Harris, of Cornell 

 University, for field assistance and advice, and for the loan of 

 specimens, also to Professor Joseph F. Whiteaves, Paleontologist to 

 the Canadian Geological Survey, for the loan of specimens. The 

 figures were drawn by Mr. Sydney Prentice, draughtsman to the Sec- 

 tion of Paleontology, Carnegie Museum. 



ARTHROPODA. 



Subclass TRILOBITA. 



Order HYPOPARIA Beecher. 



Family HARPEDID.p: Barrande. 



Genus HARPES Goldfuss. 



Subgenus Harpina Novak. 



Harpina antiquatus Billings. (Plate lo, figure i.) 



JIarpes antiquatus liillings, 1859, Canadian Naturalist and (Geologist, volume 4, 



page 469, figure 38. 

 JIarpes aiitiqiiatics Billings, 1S63, Geology Canada, page 133, figure 67. 



Of the two species of Harpes in the Chazy limestone, the one 

 named above is the commoner, and it may be distinguished from 

 Harpina otfawacnsis chiefly by its smaller size, narrower cephalic 

 border, and more anterior position of the ocelli. In the collections 

 available to the writer this species is represented only by specimens 

 of the cephalon, no trace of the thorax or pygidium having yet been 

 found. The cephalon of an average specimen is al)out half an inch 

 long, measured from the anterior edge of the border to the tips of the 

 genal spines. The width is about the same. 



Description. 

 Cephalon nearly semicircular in front, border narrow, concave, the 

 genal angles extending back a distance equal to about half the whole 

 length of the specimen, slightly incurved at the posterior ends. Eyes 

 small, simple, situated on the highest point of the cheeks and opposite 

 the anterior fourth of the glabella. Eye lines sharp and prominent. 



