Descriptions of some JapaMcse Hymeuoptera ; by Francis 

 Walker, Esq. 



Considering the earth without reference to the human 

 race, Asia and Europe may l^e regarded as one Continent, 

 which surpasses all others in size, and displays in the 

 Northern hemisphere by far tlie greatest expanse on the 

 surface of the land, and affords tlie greatest facilities or 

 the fewest obstacles to tlie migration and diffusion of 

 species. At each end of tliis region there is a group of 

 islands — the British Isles on the west and the Japanese 

 Isles on the east ; and they mark the extremes of difference 

 in the insect races which inhal)it this extent. The distance 

 between the two groups occupies nearly half of the circle 

 of longitude there, and the British Isles are much more 

 contiguous to North America ; but the Atlantic is now 

 fixed between them, and it has been supposed that some 

 of the Insect-Fauna which Europe and North America 

 had in common has passed away in the former country by 

 means of change of climate, of elevation, or of aspect in 

 the region, or by the expulsion or extermination of some 

 kinds by other kinds. Previous to makmg some notes on 

 a few groups of insects in the longitudinal range of Northern 

 Asia and of North America, I have in this communication 

 recorded twenty-four Japanese Hymenoptera, for which I 

 am indebted to Mr. F. Smith, of the British Museum. 



ICHNEUMONIDAE. 



1. Ichneumon alhidipcs. 



Male. Black, shining, thickly and very minutely punc- 

 tured. Antennae slender, much shorter than the body. 

 Areas of the metathorax well defined. Abdomen sub- 

 clavate, slightly petiolated, very much longer tlian the 

 thorax ; hind border of the second segment whitish. Four 

 anterior legs whitish excepting the coxae ; middle femora 



