296 



SCIENCE. 



[N. S. Vol. XXIV. No. 610. 



above mentioned examples varies in rela- 

 tion, being in contact with: (a) the hy- 

 pophysis (ingrowth of skin) ; (&) Sessel's 

 pocket (outgrowth of enteron) ; or (o) the 

 first mesodermic head cavity (derivative 

 from enteron). The last condition, found 

 in shark, may be the typical one. 



Importations of the Gipsy Moth . and 

 Brown-tail Moth Parasites from Europe: 

 L. 0. Howard, U. S. Department of 

 Agriculture. 



In the late spring of 1905 the state of 

 Massachusetts appropriated ten thousand 

 dollars a year, for three years, to be ex- 

 pended in an effort to import into the 

 United States the European parasites of 

 the two destructive insects mentioned in 

 the title. The larger part of this appro- 

 priation, together with a small appropria- 

 tion of twenty-five hundred dollars, made 

 by the general government, was used and is 

 being used in this attempt, the whole Euro- 

 pean end of the effort having been placed 

 under the control of the speaker. 



In June, 1905, he visited Europe, land- 

 ing at Naples on the fifteenth of that 

 n;ionth. At the time, the south European 

 brown-tail moths had all issued, and the 

 gipsy moth was in the full-grown cater- 

 pillar stage. Arrangements were made 

 with experts in Italy, in Austria, in Hun- 

 gary, in South Germany, Switzerland and 

 France to send to Boston full-grown larvae 

 and pupse of the gipsy moth; and full in- 

 structions were given as to methods of ship- 

 ment. During the following summer 

 months very many specimens were received 

 in Boston and were cared for in a tempo- 

 rary laboratory at Maiden and a number of 

 different species of parasites issued, the 

 most promising ones being tachina flies. 

 These over-wintered successfully in Massa- 

 chusetts, and a certain proportion of flies 

 issued from the over-wintering puparia the 

 present spring. 



In April, 1906, the same journey was 

 practically repeated, the speaker visiting 

 first France, then Italy, then Austria and 

 Hungary, and afterwards Germany and 

 Switzerland, and arrangements were made, 

 at an earlier period in the season, so that 

 much larger quantities of both species will 

 be secured. Shipments from many points 

 in Europe are already being received and 

 many parasites are being bred from Euro- 

 pean specimens of both species. 



The most interesting feature of the effort 

 so far has come through the wholesale in- 

 troduction of the over-wintering nests of 

 the brown-tail moth. On the strength of 

 an unpublished observation of Jablonowski, 

 of Budapest, mentioned to the speaker in 

 July, 1905, no less than one hundred and 

 eighty-five thousand n^sts were imported 

 into Massachusetts from forty different 

 localities in Europe, ranging from Rennes 

 on the northwest to Budapest on the south- 

 east. From these nests were bred the pres- 

 ent spring and early summer many thou- 

 sands of specimens of parasites of different 

 groups; these have been colonized in the 

 open and in out-door cages constructed of 

 wire gauze and placed over good-sized trees 

 thoroughly infested with both gipsy moth 

 and brown-tail moth larvas. 



The interesting feature of the experi- 

 ment is the large scale upon which it has 

 been conducted. Earlier attempts to in- 

 troduce and acclimatize beneficial species 

 from one part of the world into another 

 have been done on a small scale; but com- 

 paratively few have been imported at any 

 one time. In this instance the experiment 

 was so perfectly safe and the country into 

 which the forms were introduced was so 

 extensively ravished by the insects that the 

 introduction of additional pests of the same 

 species could possibly do no harm ; whereas, 

 by such wholesale introduction, vastly 

 greater numbers of the parasites would be 



