334 DAVENPORT ACADEMY OF NATURAL SCIENCES. 



during the early summer, giving its attention mainly to the young larvae 

 of the bark lice, of which it destroys great numbers. When about to 

 pupate, the larva attaches itself to the bark, and the skin then dries and 

 splits along the back partially disclosing the pupa within. Large groups 

 of these pupse are often seen about the junction of the larger branches 

 with the trunk. These are often regarded by the ignorant as but a dif- 

 ferent form of the bark louse, and are ruthlessly destroyed by them. 



2. Huperaspis signata, Oliv., a lady beetle of very similar form and 

 appearance to the last, but of about half the size and with the red spots 

 on the elytra entirely circular in form. The larva however, is very dif- 

 ferent, of a whitish color, covered with a white downy substance, and 

 dwelling habitually in the egg nests of the Pulvinaria. Often two or 

 more of these larvse are found in a single nest, and do great havoc 

 among the eggs and newly hatched bark lice. Egg nests containing 

 tiiese larvae can generally be recognized by being partially separated 

 along the median line, and later by their flabby appearance. These 

 larvae are occasionally seen to migrate from one nest to another. When 

 ready to pupate they leave the egg nest and descend the tree in search of 

 some crevice wherein to undergo their transformations. While on this 

 search they often wander a considerable distance, and thus sometimes 

 prove a possible means of spreading the Pulvinaria. Like the Chiloc- 

 oriis they are often mistaken for the bark-lice themselves, and unwit- 

 tingly destroyed. Mr. Riley informs me that he has also raised Hyper- 

 aspis biyeminata. Rand, from specimens furnished by me. 



3. I have several times observed a small black species of Scymnus on 

 the twigs, and a small larva probably of the same dwelling in the egg- 

 nests, like the last species. 



4. Anatis lo-puncMta, Olivier, both imigo and larva, I have found in 

 small numbers feeding upon this Pulvinaria. 



5. The larva of a species of Chrysopa I have frequently observed 

 feeding upon the young lice. They probably injure as many by wounds 

 from their long mandibles as they actually devour. 



6-7. The larva; of two species of Eeduvidm have been observed prey- 

 ing upon them. 



In addition to the above enemies Miss Smith mentions an Acarus. I 

 have never observed an Acarus upon a Pulvinaria., but I have found 

 them often excessively abundant under the scales of an Aspidiotus oc- 

 curring on the same twigs.* 



MANNER OF DISTRIBUTION. 



The manner in which this insect is transported from tree to tree, and 

 from place to place is a matter of some economical interest. The young 

 lice are able and do move about quite actively. They can easily crawl 



*Prof. J. H. Comstock lias recently described (Prairie i*'ar»i«/% Oct. 2.5tli, 1879), a lepi- 

 dopterous insect under the name oi Dakruma coccidivora, the larva of which dwells in the 

 nests of Pulvinaria innurnerabilis, and constructs tubular passages out of the waxen fibers. 

 I have never observed any traces of this msect in this locality. It apjiears to be allied to the 

 bee moth (Gallerio) in its babitx, and it occurs to ine that its attraction in the egg-nests of 

 Pulvinaria may be the waxen fibers and dust rather than the eggs themselves. 



