OF HARTING. 369 



like the mandibles, varies very much in its length and 

 form according to the requirements of the different 

 species, is capable of being bent back under the head, 

 and is only exserted at the will of the insect. As a 

 rule the legs are of moderate length and slender, and 

 in the wood-boring and burrowing species, as well as 

 those which collect pollen, they are provided with 

 various suitable appendages, spines, hairs, fringes, and 

 plates. The females are supplied with instruments for 

 oviposition of different forms, severally adapted to the 

 substances in which, or on which, their instinct teaches 

 them to commit their eggs. Some carry saws, others 

 borers, and in the social groups, as everyone knows 

 who has incurred the active displeasure of a bee, a 

 common wasp, or a hornet, the ovipositor becomes a 

 weapon which is capable of inflicting an unmistakeably 

 painful wound. 



The family of Saw-flies is the first in this order, and 

 contains many genera, several species of which we 

 have found here. Their larvae are sometimes very 

 destructive, feeding on the leaves of various plants, 

 like the caterpillars of moths and butterflies, to which 

 they bear no little resemblance. The female of the 

 perfect insect is provided with an ovipositor of a very 

 complex structure, and as we possess a micro-photo- 

 graph of a specimen, we will attempt a short descrip- 

 tion of it. It consists of two nearly-transparent narrow 

 lamellae, slightly curved upwards at their extremities, 

 and crossed at regular intervals with fine sharp ridges, 

 terminating on the lower edges in very minute denti- 

 culations. Each plate is divided longitudinally by a 

 mid-rib running from one extremity to the other, the 

 lower division is the saw-blade, the upper one the 

 saw-frame, and the mid-rib itself contains the groove 

 in which the saw-blade is made to work to and fro by 

 appropriate muscles. These delicate instruments when 

 at rest are applied, between two larger plates, closely 

 to each other with their serrated edges downwards, 



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