521 



in which Black Leaf 40, at a strength of 1 pt., 1| pts., or 2 pts. to 100 gals, 

 water, either alone or in combination with soap or lime-sulphur, was 

 applied, in the case of apples, immediately before and after flowering, 

 and in the case of pears, immediately after flowering and again five 

 days later. Examination soon after spraying showed the presence 

 of numerous dead, but no living nymphs on the trees. Examination 

 two days later, however, showed many living nymphs to be present. 

 Control measures must therefore include the spraying of the trees, the 

 destruction of weeds which may serve as host plants, and the banding 

 of the trees with tanglefoot to prevent fallen nymphs from reascending 

 the trunks. Pruning should be properly carried out, so that all parts 

 of the tree may be reached by the spray. 



Crawford (H. G.). A Capsid attacking Apples {Neurocolpus 

 nuhilis, Say.) — idih Ann. Rep. Entom. Soc. Ontario, 1915, Toronto, 

 1916, pp. 79-88, 6 figs. [Received 10th October 1916.] 



The following Capsids attack apples in the Province of Ontario : — 

 Neurocolpus nuhilis, Lygidea mendax, Heterocordylus malinus, and 

 Paracalocoris colon. Of these, only the first two are of much economic 

 importance. N. nuhilis has also been recorded from Quebec, New 

 York, New Jersey, Maine, Colorado, California, Florida, and Panama. 

 The eggs are deposited either singly or in pairs in the tissue at the base 

 of a bud and in the axils of the leaves on new twigs of apple and 

 .sumach. Egg-laying probably extends over a period between about 

 15th July and 1st September, although the majority are deposited by 

 15th August. In 1915, hatching began about 27th May and the maxi- 

 mum emergence took place between 5th and 9th June, while isolated 

 individuals appeared until about 13th July. The period of maximum 

 emergence thus corresponded with the closure of the calices and the 

 early development of the fruit of the apple. The duration of the 

 nymphal stage was approximately a month, the first adult being seen 

 on 30th June. An increase in the number of adults occurred until 

 15th July ; after remaining constant for about two weeks, the numbers 

 gradually declined, until all had disappeared by 7th September. 

 Young nymphs were found on the underside of leaves and in unopened 

 and rolled leaves. When the fruit reached a diameter of about | inch, 

 the leaves were deserted and attacks on the young apples continued 

 for about 10 days. At the end of this time, the majority of the nymphs 

 migrated to food-plants at the base of the trees, these plants including 

 red clover, curled dock, alsike clover, Canada blue grass, rye, evening 

 priim-ose, etc. The majority of adults appeared on these hosts, and 

 after remaining for about a week in this position, a small proportion 

 appeared on the trees and fed on the buds in the leaf axils. Injury to 

 the young fruit by the nymphs results in the formation of raised areas 

 over the point of puncture. When these are very numerous 

 deformation and stunting takes place. In one case, injured fruit 

 rotted and fell, probably as the result of inoculation by the bugs with 

 the spores of Bacillus amylovorus. The feeding of the adults leads to 

 the death of many buds, and in cases where the twig is punctured, to the 

 formation of a gall. 



(C327) O 



