Cjje ffHuaiian Entomologist. 



VOL. XIV. LONDON, ONT., MAY, 1882. No. 5 



ENTOMOLOGY FOR BEGINNERS. 



" LONG-ST/NOS.' 



BY W. HAGUE HARRINGTON, OTTAWA, ONT. 



Among the conspicuous insects which attract the attention of even 

 non-entomologists, there are few more interesting in their structure and 

 habits, as well as in their relations to other groups, than the large " long- 

 sting " ichneumons with their long triple "tails." Our two largest species 

 belong to the genus Rhyssa (of the Hymenoptera), and as, so far as I am 

 aware, no accounts of them have yet been published in the Entomolo- 

 gist, a brief description of their appearance and habits may not be 

 undesirable. 



They may be easily distinguished from their relatives (often their 

 victims), the " horn-tails " — Uroceridae — as they are much more slender 

 in body and appendages. The female, readily determined by the extra- 

 ordinary development of the ovipositor, has the abdomen stouter than that 

 of the male, with the posterior segments dilated and curved under, and 

 bearing the ovipositor, which is constructed essentially of the same parts 

 as is that of a " horn-tail," only that they are greatly lengthened. 



The head, in shape Uke a short segment of a cylinder, slightly convex 

 before and concave behind, bears on its rounded front a pair of large 

 eyes, from between which spring the long slender antennae. The head is 

 joined by a small neck to the thorax, which is strongly built and supports 

 two pairs of long narrow wings, as well as the six very long and slim, yet 

 strong, legs. The segment of the abdomen which adjoins the thorax is 

 much less in diameter than the succeeding ones. 



The male has a long cylindrical abdomen tapering gradually to the 

 extremity. This, in connection with the prominent head and narrow 

 wings, gives him, especially when in flight, a considerable resemblance to 

 a dragon-fly, from which, however, he is at once distinguished by his long 

 antennae and shorter hinder wings. 



