i i 
/ of {lie United States Gavemakaot 
Issuod Juno .'50, L9G8. 
U. S. DEPARTMENT OF AGRICULTURE, 
BUREAU OF ANIMAL INDUSTRY— BULLETIN NO. 39. 
A. D. MELVIN, Chief of Bureau. 
INDEX-CATALOGUE 
OF 
MEDICAL AND VETERINARY ZOOLOGY. 
PART 20. 
[Authors: N to Nystrom.] 
BY 
CH. WARDELL STILES, Ph. D., 
Consulting Zoologist of Bureau of Animal Industry; Zoologist of U. S. Public 
Health and Marine-Hospital Service, 
AND 
ALBERT HASSALL, M.R. C.V. S., 
Assistant in Zoology, Bureau of Animal Industry. 
WASHINGTON: 
GOVERNMENT PRINTING OFFICE. 
I908. 
