17 



the last one or two segments of the abdomen, where it is allowed to 

 remain. The pupa is of the usual form and of a very pale yellow color, 

 except that the back and under side of the abdomen is tinged with 

 orange yellow. The entire pupa is thinly covered with short light yel- 

 lowish hairs. It measures about one-ninth of an inch in length. One 

 of these larva assumed the pupa form on the 14th of July and was 

 changed to a beetle six days later. 



I have seen numerous thickly infested oranges and lemons upon each 

 of which were from two to half a dozen of these larvae, while the scales 

 were so torn up as to give the infested fruit a roughened appearance 

 very noticeable upon a slight inspection. I have also found this larva 

 upon apple trees infested with the Woolly Aphis (ScMzoneura lanigera 

 Hausm.), and in such cases the larva frequently attaches to the bris- 

 tles on various parts of its body portions of the woolly substance taken 

 from the bodies of its victims. 



Besides the larvae of these two ladybirds, I have also seen the larva of 

 the California Lace- wing (Chrysopa calif ornica Coq.) feeding upon the 

 Eed Scale. Almost every fruit-grower in southern California is famil- 

 iar with the appearance of these active, pale gray larvae which have 

 somewhat the appearance of miniature alligators, and provided with a 

 pair of long, slender, pincer-like jaws projecting some distance in front 

 of the head. In attacking a Eed Scale this larva inserts its right man- 

 dible, or jaw, beneath the scale, then presses the tip of its other mandible 

 against the upper side of the scale, thus bringing the scale-insect be- 

 tween the tips of its mandibles; in this way it extracts the juices of the 

 scale through its right mandible which, being hollow, answers this pur- 

 pose admirably. These larvae feed upon a great variety of insects and 

 their eggs, and even do not hesitate to attack each other, the stronger 

 attacking and devouring or rather extracting the juices of the weaker 

 ones, while the latter take this proceeding as a matter of course, never 

 so much as making the least show at resistance. It is doubtless largely 

 due to this cannibalistic propensity of theirs that these highly benefi- 

 cial insects do not become more numerous and render greater service to 

 the horticulturist by destroying the noxious insects that infest his trees 

 and plants. Their numbers are also still further decimated by the at- 

 tacks of internal parasites. From the larvae and pupae of this Lace- 

 wing I have bred no less than four different kinds of these parasites, 

 only one of which, the Isodromus iceryce Howard, has as yet been de- 

 scribed. These parasites seldom issue until after the Lace- wing larva 

 has spun its cocoon. The parasitic larvae spin no cocoons of their own, 

 but assume the pupa form within the cocoons of their hosts, and, after 

 being changed to the perfect or winged state, they gnaw irregular 

 holes usually in one end of the cocoon, out of which they escape. I 

 have bred two of the parasitic Isodromus from a single pupa of the 

 Lace- wing, while from another pupa issued sixteen specimens of an 

 undetermined species of Tetrastichus, Of the other two kinds of para- 

 2i382— Ko. 26 2 



