LIFE HISTORY NOTES ON CRANBERRY LAKE 

 HOMOPTERA 



By Herbert Osborn 



111 connection Avith studies of the ecology of the IToiiioptera of 

 tlie Cranberry Lake region it was possibh^ to secure a nuraher of 

 records on the development of some of the species and, while these 

 do not cover as long a period of the year as would be desirable 

 for all purposes, the fact that for many species the summer months 

 include the main events in the life cycle seems to warrant the 

 ]niblication of the records even if less complete than would be 

 desired. From the author's standpoint this appears the more 

 desirable because there is little probability that circumstances will 

 permit him to work at periods necessary to complete the annual 

 life cycles and the facts given here maj' serve as a basis to facilitate 

 further studies. Also it is believed that the facts gained may 

 serve for such appreciation of the injurious phases of the insect 

 as to encourage working out practical measures for control. Tn 

 some instances, if not all, the determination of certain fragments 

 of the life history appears to supply a biological basis for tlie 

 tlevelopment of preventive or remedial measures which may be of 

 service in the protection or conservation of the forest resources. 



BIRCH TREE=HOPPER 

 Carynota stupida AValker 



This species (Plate III) often occurs in large numbers on yellow 

 birchj but its presence would scarcely be suspected since the insect 

 is so perfectly protected by form and color that it is hardly 

 l)ossible to see them even when their position has been noted. 



The nymphs occur almost invariably in the axils of small twigs, 

 mostly on branches of one year's growth, the head pressed closely 

 against the base of the twig, the body lying flat and lengthwise 

 on the branch, the tail usually toward the tip of the branch 

 (Fig. h, Plate III). Here they remain apparently immovable' 

 for long periods of time, the food supply being drawn doubtless 

 from the cambium of the growing twig. They are very commonly 

 attended by ants, so far as observed all of one species {Form>ca 

 sanguivea Latr. sub. sp. ruhicunda Emerj'*) ; and by far the easiest 

 way to locate the nymphs is to look for the ants and note the 

 nymphs which they are attending. The nymphs appear absolutely 

 oblivious to the movements of the ants, although the frequent 

 rubbing and " caressing " which they receive would seem to be 

 sufficient to disturb them. The nymphs, however, appear to be 

 very difficult to disturb, seeming to be glued to the twig, and only 



* Identified by Dr. M. W. Wheeler, Harvard University. 



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