1917] ECONOMIC ZOOLOGY — ENTOMOLOGY. 657 



ing the fly-breeding capacity of the open farm manure heap as distinguished 

 from heaps in close proximity to dwellings. The conclusions drawn which 

 apply to manure heaps far distant from houses are as follows : 



While the house fly is liable to breed in large numbers in stable refuse which 

 is stored in close proximity to dwellings, the governing factor is found in the 

 dwellings rather than in the manure heap, the latter merely serving as a 

 secondary convenience, providing a breeding place for the flies which have been 

 attracted to the houses in search of food. The open farm manure heap far 

 away from houses is but little frequented by house flies, and then only later in 

 the season when the insect has become numerous and widely dispersed. The 

 spent manure heap, in which fermentation has practically ceased, produces 

 under rural conditions at least practically no flies at all. Although the farm 

 heap may produce but few house flies, it is a prolific source of Stomoxys cal- 

 citrans, and those agriculturists who value the comfort and health of their 

 animals .should treat all manure with a view to the destruction of the larvae 

 of this pest. 



A note on some helminthic diseases with special reference to the house fly 

 as a natural carrier of the ova, T. O. Shikcore (Parasitology, 8 (1916), No. 3, 

 pp. 239-2Jf3) .—The data presented show the house fly to be an important factor 

 in the conveyance of the ova of helminths. 



niariasis. — Report of two cases in the District of Columbia and analysis 

 of the cases reported for eastern North America, IM. W. Lyon, Jk. (Jour. 

 Amer. Med. Assoc, 68 (1917), No. 2, pp. 118, 119). — In reporting upon two cases 

 of infection with Filaria bancrofti In the District of Columbia it is pointed out 

 that Culex quinquefasciatus, the mosquito which serves as the intermediate 

 host of F. bancrofti, ranges as far north as Washington and St. Louis, and per- 

 haps farther. 



A new enemy of maguey, G. Gandaka (Mem. y Rev. Soc. Cient. "Antonio 

 Alzate," 32 (1915), No. 11-12, pp. 483-489, figs. 5).— An account of (Trypeta) 

 Myennis scutellaris, which is a source of injury to the agave in Mexico. 



The cabbage root maggot and its control in Canada, with notes on the 

 imported onion maggot and the seed-corn maggot, A. Gibson and R. C. Tre- 

 HEKNE (Canada Dept. Agr., Ent. Branch Bui. 12 (1916), pp. 58, pi. 1, figs. 29). — 

 This bulletin reports studies of the biology of the cabbage maggot and of 

 control measures made at Agassiz, British Columbia, and at Ottawa, Ontario. 

 It records observations made of the depth of puparia in the soil, emergence 

 of flies from puparia buried at difi'erent depths, the length of the puparium 

 stage during summer and autumn, length of the life of individual flies, develop- 

 ment, habits, and reproduction, and gives a chart which shows the egg de- 

 position of the cabbage maggot at Agassiz in 1915, with records of prevailing 

 temperature, rain, etc. 



Short accounts of the life history, habits, and reproduction of the imported 

 onion maggot or Hylemyia antiqua (Phorbia cepetorum) and of the seed-corn 

 maggot (P. fusciceps) follow. 



The means of controlling root maggots considered include the use of tar 

 paper disks (B. S. R., 31, p. 352; 85, pp. 53, 55), cheesecloth frames (E. S. R., 

 25, p. 38), trap crops, etc. The bulletin concludes with a discussion of the 

 control of root maggots under field conditions. 



The parasites of maggots reared in Canada are a staphylinid (Baryodma 

 ontarionis), long known in eastern Canada as an enemy of the cabbage root 

 maggot; a cynipid (Cothonaspis gillettei), which has a wide distribution in 

 the Dominion; a chalcidid (Pachycrepoideus dubius) ; and Vv'hat is thought to 

 be Hemiteles ruflcoxus. The predators, which were found under laboratory 

 conditions to readily devour the eggs, larvae, and often the hard-shelled puparia, 



