2 4 REPORTS OF OBSERVATIONS AND EXPERIMENTS. 



moths from these issue during the month of April. A second brood 

 issues in August, while the third ana last brood of the season makes 

 its appearance in November and during the first half of December. 



Both sexes are winged and it would therefore be quite useless to place 

 obstructions around the trunks of the trees, as is sometimes practiced 

 in dealing with those kinds of span-worms which are wingless in the 

 female sex; moreover, as already stated above, the larvae of the present 

 species assume the chrysalis form on the tree instead of entering the 

 earth, and this habit of itself renders the above-mentioned method 

 entirely useless in dealing with this species. 



Whenever these span-worms appear in destructive numbers, about 

 the only practical remedy we are able to suggest is to spray the infested 

 trees with Paris-green solution, composed of one pound of Paris green 

 thoroughly stirred into 200 gallons of water. If a small quantity of 

 soap is added to the solution this will cause it to spread more evenly 

 over the tree. It should be borne in mind that a very small quantity 

 of this poison will prove fatal to the recently-hatched span-worms, 

 whereas the nearly full-grown ones will be able to withstand a much 

 larger quantity of the poison. Hence the importance of applying the 

 poison while the span-worms are still very young. 



The Orange Leaf -roller (Tortrix citranaYevn). — This is a small, greenish 

 caterpillar that ordinarily lives in a rolled or folded leaf, upon which it 

 feeds, but it also has a habit of burrowing into the green oranges, caus- 

 ing them to turn prematurely yellow and finally to drop from the tree. 

 I first obtained specimens of this insect on the 6th of May, 1885, and 

 since that time have occasionally met with it, although never in large 

 numbers. Last season, however, it appears to have been quite plentiful, 

 judging from the number of letters received asking for information con- 

 cerning it. 



Although ordinarily met with upon orange trees, I have also found 

 this leaf-roller upon apricot, willow, oak {Quercus agrifoUa),Y?i\& wal- 

 nut (Juglans californica), and golden-rod (Solidago californica). 



The larvae which live in the oranges desert their burrows and creep 

 into some sheltered place when about to pass through their transforma- 

 tions, but those which live in rolled or folded leaves assume the 

 chrysalis form within such leaves. 



. The time passed in the chrysalis state varies greatly according to 

 the season of the year; my notes show that five of the chrysalides 

 remained in this state 9, 11, 11, 12, and 19 days, respectively. There 

 are doubtless four or five generations each year. I have found this 

 insect in some stage of its growth during the months of January, March, 

 April, May, June, and September, but it is most abundant in early 

 summer. The species was described by Prof. 0. H. Fernald, in LJntomo- 

 Jogica Americana (vol. V, p. 18), from specimens bred by the writer. 



Two different kinds of internal parasites are known to me to attack 

 this insect. The first of these is a small, black, four- winged fly belong- 

 ing to the Microgastrinae. The larva of this parasite when full-grown 



