34 IMPORTED PARASITES. 



the Blepharipa maggot (Fig. 11) reaches maturity and works 

 its way out of the now empty shell. It then drops to the earth 

 ' and burrowing its way several inches below the surface, trans- 

 forms to a puparium (Eig. 12), an oval, dark body, formed of 

 the hardened skin of the larva, and containing the true pupa. 

 This pupa remains unchanged during the winter, and produces 

 the perfect fly in the late spring following. 



Blepharipa is a very important parasite of the gypsy moth 

 in Europe, and in western Europe appears to be very much more 

 destructive than does the Glyptapanteles. It is represented in 

 Japan by another very similar species (Crossocosmia sp.), the 

 adults of which have not yet been reared at the laboratory. 



The difficulties which have stood in the way of the successful 

 introduction of this parasite into America have been different 

 from any that have hindered the work with any other species. 

 Importation of the full-grown caterpillars or freshly formed 

 pupse of the gypsy moth resulted in 1905 in securing a con- 

 siderable mimber, several hundred at least, of the hibernating 

 puparia, but not a single fly issued the following year. The 

 cause was not obvious at the time, but Avas later determined to 

 be due to the drying up of the pupse within the puparium. 

 Death did not immediately ensue, but eventually the fly would 

 die when it was nearly ready to issue. A great many different 

 methods of hibernating these puparia have been attempted, and 

 with very variable but uniformly unsatisfactory results. Dur- 

 ing the winter of 1907-08 the puparia were kept ih moist earth, 

 and a 10 per cent, emergence from a total of 5,000 was secured. 

 The year before it was less, hardly equalling 3 per cent., and 

 the year following much less, hardly amounting to 1 per cent. 

 These tremendous losses were unexplained until the summer of 

 1909, when large numbers of gypsy caterpillars were received 

 in a living condition from Hyeres, France, through the mag- 

 nificent efforts of M. Rene Oberthiir of Rennes, and as a direct 

 result of Dr. Howard's trip to Europe that year. (Plate II.) 

 They came in better shape, in many respects, than any other 

 similar lot of material ever received, having been shipped in 

 cold storage on fast transatlantic liners. 



For the first time since the inception of the work, large 

 numbers of living pupee containing the immature maggots of 



