THE CANADIAN ENTOMOLOGIST. 17 



NOTES ON THE LIFE-HISTORY OF TWO SPECIES OF 



CAPSID^. 



BY C. R. CROSBY, ITHACA, N. Y. 



The brilliant red nymphs of Heterocordylus inal'mns Reut., and 

 Lygidea viendax Rent., are found during May and June abundantly on the 

 leaves and fruit of the apple in many parts of New York State. 



The eggs of both species are laid during the summer, and are inserted 

 their full length into the bark on the smaller branches, two-year-old wood 

 being preferred. The eggs are very difficult to find, and I have not been 

 able to make as many observations on them as desirable. All the eggs 

 definitely known to belong to H. mal'mus were found inserted in slits in 

 the bark at the base of the fruit spurs. As far as I have observed, the 

 normal number of eggs for each cavity is four. Each egg is 1.6 mm. long 

 by .4 mm. wide. It is rather strongly curved, slightly compressed and 

 dull whitish in colour. The embryo develops in the lower enlarged 

 portion, its head being some distance from the tip of the egg. The woody 

 tissue of the bark, especially the outer portion, adheres so closely to the 

 egg that it is impossible to remove it completely, even when hardened in 

 alcohol. 



The eggs of L. meiidax are usually inserted in pairs in the lenticels 

 of smooth two-year-old wood. They do not lie parallel to each other, but 

 diverge at a wide angle in order to avoid the solid wood, since they are 

 longer than the thickness of the bark. In size and shape they closely 

 resemble the eggs of H. malinus. 



The eggs of both species hatch soon after the opening of the apple 

 buds, and the nymphs feed on the leaves and also attack the fruit as soon 

 as it sets. In the Cornell Insectary I have reared both species to the 

 adult stage exclusively on foliage. 



As the nymphs grow older they become more active, and when 

 disturbed retreat to the twig, where they adroitly dodge to the opposite 

 side like a squirrel. They will frequently drop suddenly, but rarely fall 

 to the ground, usually alighting on another branch. They have a curious 

 way of getting a new hold. The posterior end of the alimentary canal can 

 be extruded, and is covered with a viscid secretion. As soon as they 

 strike an object in falling, this sticky organ adheres to it until the insect 

 can regain its foothold. When confined in a glass bottle young nymphs 

 become attached in this way so firmly to the glass that they cannot escape, 

 and so perish. 



January, 1911 



