12 BULLETIN 1363, U. S. DEPARTMENT OF AGBICULTUEE 



proportionate number of larvae per locality the ratio would be 

 approximately the same. 



Hemerocampa leucostigma and Notolophus antiqua are apparently 

 double-brooded. Larvae of these species can be found in the field 

 from June until October. The periodic abundance of the former, 

 usually during the latter part of July, makes it a very desirable 

 host. X. antiqua is not at all common but what collections haye been 

 obtained usually gaye forth a few specimens of Compsilura. Stud- 

 ies made by the writers indicate that it also is a desirable host. 

 There are but few insects among those studied where the competi- 

 tion between the tachinid parasites is so keen as in Hemerocampa 

 leucostigma. From data secured by Wooldridge 6 in 1910 we find in 

 E. leucostigma, besides a great number of hymenopterous parasites, 

 seyen species of Tachinidae : " Compsilura. Phorocera clarlpennis 

 Macq.. Tachina mella Walk.. Frontina aletlae Eiley. Frontina f re fi- 

 chu Will., .{Exo-rista) Zenlllla amplexa Coq., and Winthemia quad- 

 ripustulata Fab. Of these tachinids the first four species were the 

 more numerous. The following year collections were again made 

 from this locality with similar results. 



Xo collections were received at the laboratory from 1912 to 1915. 

 In 1916 several small ones were sent from "Westerly and Xewport, 

 R. I. Only one species of Tachinidae was recovered, C ampsilura 

 concinnata. In 1917 five collections were received from points in 

 Rhode Island and Connecticut and from these were reared 14 Comp- 

 silura and 2 Zenillia amplexa. 



The infestation of Hemerocampa leucostigma at Westerly, R. I., 

 reached its height in 191S, and from seven collections of material 

 sent from this locality there were reared, besides Compsilura. a few 

 Tachina mella. Frontina aletlae. Phorocera clarlpennis. and several 

 unknown larviform puparia. The parasites obtained in 1918 were 

 somewhat similar to those secured in 1910 and 1911. The native 

 tachinids were far less abundant, however. 



Owing to the great decrease in the infestation at Westerly. R. I., 

 in 1919, only two small collections were received from there that 

 year. These collections gave forth 10 Compsilura and 1 specimen 

 of Frontina frenchii. It was not until 1920 that there was really 

 an abundance of the species around Boston. The results of the 

 rearings of this year were not sufficient to check the findings of 

 1910. but they show clearly that Compsilura was the most efficient 

 tachinid parasite present. In fact only one specimen of native 

 Tachinidae was obtained — Phorocera clarlpennis. 



In 1921 there was a small outbreak of Hemerocampa leucostigma 

 at Everett. Mass., near Boston. A collection of over 500 larvae of 

 various stages was received at the laboratory, and from these were 

 reared 4 specimens of Apanteles melanoscelus Ratz. and 6S tachinid 

 puparia. These puparia were all Compsilura. 



The following year collections were again made in the same local- 

 ity. Over 1.000 'larva? of various stages were collected, and from 

 these were reared two species of Hymenoptera and 67 Compsilura. 



6 Gipsv moth laboratory notes. A large outbreak of Hemerocampa leucostigma 

 occurred' around Boston. Mass.. in 1910 and 1911. Manv collections of material were 

 received at the laboratory and considerable data concerning the parasites were obtained. 



7 With a single exception (Compsilura). these tachinids were the same species as those 

 reared bv L. O. Howard at Washington, D. C. in 1S97 (6). 



