ECONOMIC ZOOLOGY — ENTOMOLOGY. 459 



Graham-Smith, H. B. Fantham, and Annie Porter (pp. 3^56) ; The Life His- 

 tory of N. apis, and the Significance of the Various Stages of the Parasite in 

 the Disease, by H. B. Fantham and Annie Porter (pp. 57-78) ; Experimental 

 Infection with N. apis: (a) Earlier Infection Experiments, by H. B. Fantham 

 and Annie Porter (pp. 79-81), and (b) Infection Experiments Carried out 

 During 1911, by G. S. Graham-Smith and G. W. Bullamore (pp. 81-94) ; The 

 Ways in Which the Disease may be Spread, by G. S. Graham-Smith and G. W. 

 Bullamore (pp. 95-118) ; Some Field Observations on Natural Methods of 

 Infection, by H. B. Fantham and Annie Porter (pp. 119-122) ; Examinations of 

 Certain Insects Found in Hives, by II. B. Fantham and Annie Porter (pp. 123, 

 124) ; Treatment and Prevention, by G. S. Graham-Smith and G. W. Bullamore 

 (pp. 125-129) ; Microsporidiosis in Other Hymenoptera : (a) Infection Experi- 

 ments, by H. B. Fantham and Annie Porter (pp. 130, 131), (b) Observations on 

 Humble Bees, by H. B. Fantham (p. 131), and (c) Infection Experiments and 

 Observations, by G. S. Graham-Smith (pp. 131, 132) ; Bacteriology of the Dis- 

 ease, by W. Maiden (pp. 133-137) ; and Note on Certain Protozoa Found in Bees, 

 by H. B. Fantham and Annie Porter (p. 138). 



A contribution to the embryology and to the biology of Apanteles glom- 

 eratus, R. Gbandori (Redia, 7 (.1911), No. 2, pp. S63-//2S, pis. J,, fig. i).— A de- 

 tailed report of studies of this braconid parasite of the cabbage butterfly (Pieris 

 trassicce). 



The pear slug (Caliroa cerasi [Eriocampoides limaclna]), R. L. Webster 

 iloioa 8ta. Bui. ISO, pp. 167-192, figs. i5).— This is a detailed report of studies 

 of the life history and bionomics and of remedial measures for the pear slug 

 (C. cerasi), a brief account of which has been previously noted (E. S. R., 26, 

 p. 863). The subject is taken up under the headings of control measures; past 

 history, destructiveness, and distribution ; food plants ; classification ; life his- 

 tory ; and natural enemies. A bibliography of 35 titles is appended. 



The slugs feed on the upper surface of the leaves, removing only the upper 

 portion and leaving the veins bare, badly injured trees appearing as if they had 

 been scorched by fire. The damaged leaves dry, turn brown, curl up, and finally 

 fall. Frequently trees ai"e entirely stripped of their foliage in midsummer. 

 Cherry trees, under such conditions, are forced to put out a new growth of 

 leaves, weakening the tree and greatly reducing the crop of fruit the following 

 year. 



There appear to be 2 generations of the insect in central and northern Iowa. In 

 central Iowa the first brood slugs appear in June and early in July and the second 

 late in July and during August, the 2 generations generally being quite distinct. 

 The winter is passed by the slugs within their cocoons in the soil. In the 

 spring they pupate, and late in May and early in June the adult sawflies emerge 

 from the cocoons and deposit their eggs under natural conditions just beneath 

 the epidermis of the upper side of the leaves of cherry, plum, and other trees. 

 The egg hatches in from 10 to 18 days and in the vicinity of Ames most of the 

 slugs have become fully grown and have gone into the soil beneath the trees 

 where they are feeding by July 4, the adult flies emerging about the middle 

 of the month. At Ames most of the second brood slugs have disappeared by 

 the middle of September, although a few straggling ones may be found after 

 that time. 



Parthenogenesis is thought to occur in this species although it has not been 

 satisfactorily proven. Large numbers of sawflies have been collected and 

 examined by the author without the discovery of a single male. The author 

 has found much variation in the number of molts passed. Thus in 14 cases 

 closely observed 5 larvte molted 5 times. 5 molted 6 times, 3 molted 7 times, 

 and 1 molted 8 times. 



