87 



were all of the family Corixidse, or "water boatmen," and similar to 

 species which are found in boreal America. We also received infor- 

 mation that the} T were on sale in a well-known bird store in the city of 

 Washington. The species were three in number, and were identified 

 by Mr. Otto Heidemann, of this Office, as JVotonecta americana Fab., 

 Corixa mercenaria Say, and C. edulis Champ., all of which are 

 described in Biologia Centrali-Americana, Hemiptera-Heteroptera, 

 Vol. II, by G. C. Champion. Writing of mercenaria, Mr. Champion 

 states that it swarms in the large lakes near the City of Mexico, and 

 much has been written about it from the economic point of view, the 

 eggs, larvae, and adults being collected and sold in Mexico as articles 

 of food, it is said, for both man and birds, while of late }^ears they 

 were even being imported into England as food for caged birds. The 

 food value of these insects appears to have been recognized since 1625, 

 by Thomas Gage who is credited with being the first English traveler 

 in Mexico. His observations have been confirmed by Say and Guerin, 

 the latter .stating that C. femorata is sold for the same purpose. 

 Immense numbers of these "water boatmen" are sometimes captured 

 on the wing toward evening. Probably all of the "water boatmen," 

 of which there are many species in North as well as Central America, 

 could be utilized for the same purpose, it being merely a question of 

 capturing them in sufficient numbers to make it profitable. 



The same month Mr. George L. Hopper, of the Bureau of Fisheries, 

 Crockett Depot, Va., furnished samples of Mexican aquatic bugs of the 

 same species above mentioned, including two other forms, one doubt- 

 fully identified as inscripta. Mr. Hopper stated that the material sent 

 for examination had just been received in several pounds in the dried 

 state for experiment as food for } T oung trout. The trout were eating 

 them and doing well, and our correspondent was convinced that it was 

 the best artificial food that had ever been used. He stated that the 

 bugs were gathered in large quantities from Mexican lakes, especially 

 Lakes Choleo and Texcoco. Their eggs are glutinous and adhesive to 

 submerged objects in the same manner as is oyster spat. He adds that 

 Corixa femorata is used in Mexico for the same purpose, and has long 

 served as an article of food for the natives of Mexico. 



Concerning the manner of use of these insects as fish food, Mr. 

 Hopper stated that as they were dry they were run through a coffee 

 mill and ground as finely as desired, after which scalding water was 

 poured over them to soften them. They were then mixed with 20 per 

 cent of mush, and this he stated made the best food for small fish 

 which he had ever seen tried, and he has had many years of experi- 

 ence in this line of work. Thus prepared he stated the cost was about 

 5 cents a pound. 



