102 



parasitic larva emerged prior to spinning, altbough it seemed probable 

 that the ventral portion of the thoracico-abdominal suture was used for 

 this purpose. Mr. William H. Patton, who has also found this parasite 

 on Megilla macuJata, informed us in 1881 that in his specimen the larva 

 had apparently emerged form a perforation in the last dorsal segment of 

 the abdomen. 



A number of free specimens of the Spotted Lady-bird were captured 

 August 24, for i)urposes of comparison, and in one individual which 

 could not be distinguished from the others in size, coloration, or activity 

 was found a larva which was with little doubt that of the same para- 

 site. This larva was apparently full-grown, as it tilled the cavity of the 

 abdomen completely. Its head was directed towards the suture between 

 the abdomen and the metathorax, thus strengthening the probability 

 that this is the point of exit. 



In addition to the numerous specimens of MegiUa macuJata found thus 

 parasitized at Washington, one specimen of Coccinella ^-'punctata was 

 also found which had evidently been infested by the same parasite. 



Mr. Webster's observations and his efforts, at our request, to ascer- 

 tain the point of exit of the parasitic larva from the beetle are sum- 

 med up in a letter dated Oxford, Ind., July 22, 1884, and from which we 

 quote : 



I am sorry to say that witli my present knowledge I am unable to settle the Lady- 

 bird parasite matter to my satisfaction. I have bad five examples, only one of which 

 (a) was placed in alcohol when found. This had suflficient vitality left to tear itself 

 from the meshes of the cocoon. From this I think the parasite escaped by way of the 

 aperture in the membrane connecting the thorax with the abdomen, which you can 

 readily see. Three of the others were dried and difficult to study, none, however, 

 exhibiting the aperture as in (a). In one the mouth was seriously danniged ; in the 

 other two not. These two were very brittle and, although there were apertures above 

 in the vicinity of the scutellum and bases of the wings, I do not like tu attribute to 

 the parasite what might have been doue by Webster. 



The adult insect was bred in some numbers both from Washington 

 and from Indiana specimens. Only females, however, were reared. 

 !N'o observations have yet been made on the mode of oviposition. 

 lleference to the literature of European parasites of Coccinellida^ shows 

 that the so-called Microctonus terminatus (Nees) has precisely similar 

 habits, and under the supposition that the American species might be a 

 Microctonns, specimens were sent to Mr. E. A. Fitch, of England, through 

 Mr. J. B. Bridgman, for comparison with identified species in England. 

 Through an oversight, IMr. Fitch did not notice that the sjiecies did not 

 belong to Microctonus, and very naturally answered ^Ir. Bridgman that 

 it did not correspond with any of Kuthe's tyi)es of this genus. 



Subsequent study indicates that the species bred by us may i)roba- 

 bly be placed in the Braconid genus Centistes of Haliday, jiulging from 

 Ilaliday's original description and the few words of analytic diagnosis 

 contributed by Rev\ T. A. Marshall to ]\Ir. Cressou's synopsis of the 

 Hymenoptera of North America. 



