

OF WASHINGTON. 227 



to the north and the south. Mr. Ashmead spoke principally about 

 the possible spread of the parasites of injurious species. In his 

 opinion parasites will always follow their hosts, no matter what 

 the spread of the latter may be. He mentioned particularly Iso- 

 cratus vulgaris and Euphorus sculptus, as well as some of the 

 parasites of wood-boring Coleoptera, which occur apparently in 

 all parts of the world. He mentioned also the Spalangia parasite 

 of the house-fly, and the fact that the European Opheltes glaucop- 

 terus, originally an European species which occurs all through 

 the United States, had recently been found by him in a collection 

 of insects from Japan. These facts, he thought, emphasized the 

 importance of efforts to introduce parasites of introduced injuri 

 ous species. 



Dr. Merriam expressed his pleasure at the opportunity of list 

 ening to the paper just read, not only on account of his long 

 study of the problem of distribution, but also because he had 

 always believed that there is a direct practical bearing of the ques 

 tion in just this direction. In 1868 he had made an appeal before 

 the New York State Legislature for the establishment of a bio 

 logical survey, arguing that when we became familiar with the life- 

 zones we could predict the spread of injurious species. He had 

 also referred to the same point in one of his official reports. The 

 paper just read, however, was the first direct proof of the cor 

 rectness of his idea which had been advanced. 



Apropos to the occurrence of Opheltes in Japan, Mr. Schwarz 

 added that it is remarkable that so few Japanese insects have 

 been introduced into California. Referring further to the sup 

 position that Aspidiotus perniciosus was introduced from Aus 

 tralia, he thought that the original home of many of our injurious 

 Coccida3 must be China. The Coccid fauna of China has not 

 been studied, but, on account of the extremely old civilization and 

 cultivation of plants, many injurious forms which have since 

 spread widely must have originated there. Mr. Ashmead" agreed 

 with the last speaker and stated that the most injurious among 

 orange-scales Mytilaspis citricola was brought direct to 

 Florida from China many years ago upon orange plants. Dr. 

 Gill stated that the most ancient civilization was not Chinese, 

 but Indian, Assyrian, and north African. Our domestic animals 



