147 



pupation lasts from 14 to IG days, and the adult escapes by gnawing 

 a hole on the upper side of the cocoon. At least two generations 

 occur in a season, the adult life generally lasting 5 or 6 days and 

 sometimes as long as 10 days. In captivity the adults fed on the sap 

 oozing from cut leaves and on honey-dew, but they seemed to live as 

 long and remain as vigorous without food. 



DicKERSON (E. L.) & Weiss (H. B.). The Life-history and Early 

 Stages of Platymetopius hyalinus, Osb., a Japanese Leaf-hopper 

 in New Jersey. — Ann. Entom. Soc. America, Columbus, Ohio, xii, 

 no. 4, December 1919, pp. 369-372. [Eeceived 9th February 

 1920.] 



Platymetopius hyalinus, Osb., has been observed to be more or less 

 abundant in New Jersey during the last few years on Japanese maple 

 {Acer palmatum). From observations made during the summer of 

 1918, when the species was abundant on the Norway maple, 

 A. jjlatanoides var. globosum, it was found that hibernation occurs in 

 the egg-stage, each egg being deposited singly just under the bark 

 close to a bud on the recent grow^th of the twig. Groups of two to 

 five eggs occasionally occurred, though they were always separated 

 from each other. Hatching began about 1st June and continued 

 for nearly a month, first-stage nymphs being found as late as July. 

 From eggs hatching in early June, adults appeared early in July, so 

 that the five nymphal stages require about one month, probably less 

 in very warm w^eather. AH nymphal stages and adults may be found 

 diu-ing the first half of July, but adults are most plentiful during late 

 July and early August. The eggs that remain through the winter 

 are then deposited. The nymphs feed on the lower leaf -surf aces 

 and seem to prefer the shaded portions of the tree. All stages of the 

 insect are described. In view of the wide distribution of Japanese 

 maple as an ornamental tree, P. hyalinus has probably been introduced 

 into many other eastern locaUties. 



Treherne (R. C). Notes on the Aeolothripidae. — Proc. Entom.. Soc. 

 Brit. Columbia, Victoria, Svstematic Series, no. 12, February 

 1918, 1919, pp. 27-33, 20 figs. [Received 10th February 1920.] 



This paper includes keys to the sub-famihes and genera of 

 Aeolothripidae as well as to the species of Aeolothrips, Hal. 



ToTHiLL (J. D.). Natural Control Investigations in British Columbia. 

 — Proc. Entom. Soc. Brit. Columbia, Victoria, Systematic Series, 

 no. 12, February 1918, 1919, pp. 37-39. [Received 10th February 

 1920.] 



It is probable that barriers within the hmits of the Dominion of 

 Canada are affecting the distribution of parasitic and predaceous 

 enemies of insects ; thus a Tachinid which for years was responsible 

 for the destruction of over 60 pet cent, of the fall webworm {Hyphantria 

 cunea) became exterminated as another parasite which was able to 

 oviposit in wet weather monopohsed its host. In a similar manner 

 the principal parasites of the forest tent caterpillar {Malacosoma 

 disstria) were indirectlv killed off bv a hght frost in June. 



