232 PARASITES OF GIPSY AND BROWN-TAIL MOTHS. 



which is the next parasite to be considered, has had the opportunity 

 which Compsilura has demanded in each instance in which it has 

 been colonized, to prove itself of value. 



ZYGOBOTHRIA NIDICOLA TOWNS. 



Pretty much everything which has been said of Carcelia may be 

 said of Zygobothria, not so much because it is similar in its habits 

 as because we have very little first-hand knowledge of its habits. It 

 probably deposits living maggots upon the body of its host or else 

 very thin-shelled eggs containing maggots ready to hatch; but this 

 is not certainly known. It always leaves its host before pupation 

 and forms a free and characteristic puparium with roughened surface 

 and protruding stigmata very unlike that of any of the other tachinid 

 parasites of the same host. 



It is not quite so common as a parasite of the gipsy moth as is 

 Carcelia and not so many have been colonized, but the colonies have 

 been very satisfactory notwithstanding, and there is about as much 

 reason to expect the establishment of this species as in the case of 

 any of the others. Like several of the others, it was not colonized 

 until 1909, and its recovery is hardly to be expected until 1911 or 

 1912, and as in the case of these others its establishment and value 

 as a parasite will very largely depend upon its ability to find a suffi- 

 cient supply of acceptable hosts. 



CROSSOCOSMIA SERICARLE CORN. 



Many years have passed since Dr. Sasaki published the most 

 interesting and surprising results of his investigations into the life 

 and habits of the so-called a uji" parasite of the silkworm in Japan, 

 and his account of the manner in which this serious enemy of that 

 insect gained access to its host was so extraordinary in the light 

 of that which was known concerning the oviposition of tachinids in 

 general as to cause the truth of his discovery to be questioned by 

 several eminent entomologists. 



His work has been most carefully reviewed in connection with the 

 investigations which have been carried on at the laboratory into 

 the life and habits of the allied species, Blepharipa scutellata, and it 

 was with much satisfaction that his account of the biology of Crosso- 

 cosmia was found to apply almost equally well in nearly all of its 

 details to the biology of the European parasite of the gipsy moth. 

 There was one important point of difference, however, in that the 

 first-stage Blepharipa was never found ensconced in the ganglion of 

 its host, while Crossocosmia, according to Dr. Sasaki, habitually 

 chooses this position. 



In 1908 quite a number of the puparia of a Japanese parasite of 

 the gipsy moth was received from that country, which, so far as 



