504 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL.84 



acter of his early travelings justify Paul Marchal's expression 

 " L'incroyable Cdyssey de Monsieur Compere." 



Since those days, by degrees, the study of the natural enemies of 

 imported insect pests has become a part of the program of every 

 project based on imported pests in the United States as well as in 

 many other countries. Work of this sort has been carried on since 

 1905, and on a very large scale, with the European and Japanese 

 natural enemies of the gipsy moth and the brown-tail moth, and with 

 a very considerable degree of success. Many species have been 

 acclimatized in America and have undoubtedly been of great assis- 

 tance in the control of these species and in the prevention of their 

 spread. Similar efforts, also on a large scale, have been made in con- 

 nection with the work against the Japanese beetle and the European 

 corn borer. Laboratories have been established in Japan for the work 

 against the first-named species, and in the south of France for the 

 work against the corn borer. Many species have been carefully stud- 

 ied and introduced, and several of them have become established, 

 with results as yet not carefully estimated but which cannot fail to be 

 of benefit. 



Some rather extraordinary things have been done with other para- 

 sites. Hawaii had made great success of this kind of work, and it is 

 safe to say that very great losses have been saved to the sugar cane 

 industry over there by the importation of parasites of the sugar cane 

 leaf-hopper and of one of the cane borers. Similar successes have 

 teen had with other insects in Hawaii. There, however, conditions 

 are particularly favorable. There is an equable, subtropical climate, 

 without any great change of seasons. Introduced forms, both of 

 animals and plants, take hold readily and flourish. Most of the pests 

 have been introduced, and when their natural enemies are also intro- 

 duced the latter flourish to a remarkal)le degree at the expense of 

 the former. 



One of the most successful experiments of this nature, that may 

 be said to have proved its value completely, was the introduction of 

 a minute parasite, Prospaltella herlesei Howard, from the United 

 States into Italy to destroy a noxious scale insect of the mulberry 

 {Diaspis pcntagoua Targ.) which threatened the extinction of the 

 white mulberry in Italy and therefore the extinction of silk culture 

 in that country. From a single sending from Washington, Bcrlese 

 and his assistants bred the original stock of these parasites which 

 have since 1906 virtually accomplished the control of the scale. 



Aphdinns niali, another little Hymenoptcrous parasite, less than 

 a millimeter in length, which lays its eggs upon the aboveground 



