— n8 — 



safely, cannot feel secure even in their tight home ; for a little 

 Braconid fly, less than an eighth of an inch in length, instinct- 

 ively enters the nest and deposits its eggs in their helpless bodies. 

 During the latter part of August we found in the nests many of 

 the little white cocoons spun by the larvae of these Braconides, 

 still attached in some cases to the dead and shriveled body of their 

 victim. From many of these cocoons the adult Braconids soon 

 emerged through little circular doors cut from one end of the co- 

 coon ; but in some cases, from an irregular hole made in the side of 

 the cocoon, there emerged a Chalcid fly of about the same size as 

 the Braconid. This Chalcid fly is no doubt a secondary parasite 

 which preys upon the parasitic Braconid larva. 



Notwithstanding the number and activity if its little foes, this 

 cherry tree pest, Hydria undulata, has become so numerous in a 

 grove of small trees, mostly wild cherry, near the insectary that 

 during the past summer the beauty of many of the cherry trees 

 was seriously marred and their growth no doubt considerably 

 checked. The remedy is simple and easily applied. Our experi- 

 ments in the insectary supplemented by field observations indicate 

 that the insect is single brooded in this state, and that most the 

 larvae leave the nest during the month of September, so that if the 

 branches containing the nests be cut off and burned prior to Sept, 

 i, the pest will soon be exterminated. 



As this insect sometimes attacks the cultivated cherry- and is 

 widely distributed ; and as the literature relating to it is scanty 

 and not accessible to most of the fruit growers of this state, it has 

 seemed desirable to record our observations on the pest and thus 

 acquaint the fruit growers with the nature of its work and the 

 means of combatting it, should the insect make its appearance in 

 their orchards. 



DESCRIPTION OF THE LARVA OF HYDRIA UNDULATA. 



Larva. — Length, T9 mm. Width, 2 mm. General color, brownish-black 

 striped with white above, flesh colored below. Head, light j-ellowish brown 

 and sparsely hairy ; tips of mandibles, anal shield, and a large spot on the 

 dorsal surface of the anal pro-legs, black ; thoracic shield, dark brown. On 

 the dorsal surface of the body there are four narrow, distinct, whitish stripes 

 extending from the pro-thoracic shield to the anal shield. The edges of 

 these stripes are much indented, often appearing like a series of more or less 

 closely united spots. A similar substigmatal stripe separates the dark dor- 

 sum from the flesh colored venter. Just ventrad of the spiracles there is a 



