274 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



Experiments are now in progress, under the immediate direction of 

 Dr. E. M. Nighbert, of this Bureau, with an arsenical dip prepared 

 in concentrated form by the Biochemic Division. A preliminary 

 report indicates that this dip will prove satisfactory in the treatment 

 of cattle for ticks, but a definite statement as to its efficacy can not 

 be made at this time. 



INVESTIGATIONS CONCERNING PARASITIC PROTOZOA. 



Bureau Bulletin 119, issued during the year, contains the results of 

 investigations concerning certain constituents of normal blood, liable 

 to be confused with parasitic organisms, a preliminary report on a 

 trypanosome {Trypanosoma americanum) commonly present in 

 American cattle, and data relative to certain other parasitic protozoa. 



Investigations relative to the Texas-fever organism have been con- 

 tinued. 



INDEX-CATALOGUE OF MEDICAL AND VETERINARY ZOOLOGY. 



Parts 24, 25, and 26 of the Index-Catalogue of Medical and Veteri- 

 nary Zoology have been issued during the year. This catalogue is 

 being prepared under cooperation between the Zoological Division 

 of this Bureau and the Division of Zoology of the Hygienic Labora- 

 tory of the United States Public Health and Marine-Hospital Serv- 

 ice, the Department of Agriculture publishing the author index and 

 the Treasury Department the subject index. Unless unforeseen cir- 

 cumstances prevent, the publication of the author index will be com- 

 pleted during the coming year. 



COLLECTION OF PARASITES. 



Many new specimens have been added to the collection of parasites 

 belonging to the Bureau, 



Numerous autopsies on various animals, wild and domesticated, 

 were performed during the year for the purpose of determining the 

 presence or absence of parasitic infestation and the relation of the 

 presence of parasites to the cause of death. 



MISCELLANEOUS WORK. 



A disease among sheep reported from North Carolina was investi- 

 gated and found to be due to roundworm infestation of the alimentary 

 tract and lungs. 



Losses among a herd of young horses in Virginia during the spring 

 of 1910 were investigated, and the trouble was found to be due 

 apparently to a heavy infestation with lice and roundworms and to 

 insufficient food. 



The usual amount of correspondence relative to parasitic diseases 

 and the identification of specimens of parasites was received and 

 replied to. 



THE EXPERIMENT STATION. 



The general character of the work at the Bureau's Experiment 

 Station at Bethesda, Md., in charge of Dr. E. C. Schroeder, superin- 

 tendent, has been similar during the past fiscal year to that of former 

 years, consisting of independent investigations, investigations in 



