ECONOMIC ZOOLOGY — ENTOMOLOGY. 559 



flgs, ^). — The author liere reports upon studies which have led her to confirm 

 the finding of Tyzzer (B. S. R., 22, p. 55) that a definite poisonous principle 

 is contained in the short barbed hairs of the larva of the brown-tail moth. 

 " This substance is secreted by certain specialized hypodermal cells and is 

 liberated in the blood through the sharp basal point of the hairs when they 

 come in contact with the human skin. The poison glands are larger and fewer 

 in number than the cells which form the hairs, there being one poison cell for 

 each papilla on the tubercle instead of one for each hair." 



Life history of tlie codling moth in Maine, E. H. Sieglee and F. L. Siman- 

 TON {U. S. Dept. Agr. Bui. 252 {1915), pp. 50, pis. 2, figs. 9).— The studies here 

 reported, which form part of an investigation of the codling moth carried on 

 by the Bureau of Entomology of this Department throughout the United States 

 (E. S. R., 33, p. 61), are based upon work at Winthrop, Me., during the seasons 

 of 1913 and 1914. It is stated that the methods of study have been essentially 

 the same for the several States where the work has been undertaken. 



The seasonal history studies of 1913 are first reported in detail (pp. 3-28), 

 followed by those of 1914 (p. 28^G). A comparison of the life history of the 

 codling moth during the two seasons, including a diagram of the seasonal 

 history, follows. Much of the data is presented in tabular form. 



It was found that in Maine the codling moth has one full generation, a very 

 pmall percentage (1 to 2 per cent) of the individuals of which transforms to 

 make a partial second generation. Pupation of the overwintering larvte com- 

 mences about the middle of May and extends to the first part of July. The 

 length of the spring-brood pupal stage was found to average 21 days. Moths of 

 the spring brood commence to emerge about two weeks after the petals have 

 fallen and continue to issue for a period of about a month. The average time 

 from the date of the emergence of the moths to the first oviposition was about 

 four days. The oviposition of the spring-brood moths averaged 14 days. The 

 average length of life of males of the spring brood was about 12 days, and of 

 the females of the spring brood about 13 days. 



" The earliest first-brood eggs were deposited approximately three weeks after 

 the petals dropped. The incubation period of the first-brood eggs averaged 

 eight days. The first-brood eggs began to hatch in from four to five weeks after 

 the petals had fallen. The transforming larvae of the first brood fed for a 

 period of about 22 days. The overwintering larvae of the first brood had an 

 average feeding period of 28 days. The female larvae of the first brood fed for 

 a longer period than the male. The average time spent by the transforming 

 larvae in constructing their cocoons was a:bout 6 days. 



"Approximately from 1 to 2 per cent of the first-brood larvae transformed 

 to first-brood pupa?. The remainder of the larvae did not transform until the 

 following spring (spring pupae). Pupation of the first or summer brood com- 

 menced during the latter part of July. The average length of the first-brood 

 pupal stage was 15 days. The first or summer brood of moths began to emerge 

 just previous to mid-August and continued to issue for a period of about one 

 month. Oviposition by moths of the first brood began about mid-August. The 

 life cycle of the first generation was 51 days. The complete life cycle was about 

 55 days. 



" The average incubation period of the second brood of eggs was 11 days. 

 The average feeding period of the second-brood larvae was 46 days. The female 

 larvae of the second brood fed for a longer time than the male. 



" The hymenopterous parasite Ascogaster carpocapsw was frequently reared. 

 The well-known beetle enemy Tenehrioides corticalis was commonly found at- 

 tacking codling moth larvae. 



