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INSECT ODDITIES.-II. 



By E. A. Butler, b.a., b.sc. 



In our last paper, some of the oddities of insect life were 

 selected from that single order which is so prolific in 

 queer creatures, viz., the Hemiptera, In the present one, 

 our selection will be made from the rest of the insect 

 world, so far as it is represented in the British Isles. But 

 before entering upon the description of these additional 

 oddities, it may be worth while to point out that another 

 very excellent examjjle would have been taken from the 

 order Hemiptera, had it not been already dealt with in a 

 previous number of Knowledge. If the reader will turn 

 to Vol. XVII., p. 148, he will there find a short account 

 of the insect called Orlhezia iirticse, a fairly common species 

 belonging to the so-called scale-insects, and one which, at 

 least in the female sex, looks more like a piece of sculpture 

 in alabaster, or a cast in plaster of Paris, than a living 

 insect, and it is well worthy of a place in our gallery of 

 oddities. 



Turning now to the order Hymenoptera, that of the 

 bees, wasps and ants, we will select a curious creature 

 belonging to a small section of the order called Procto- 

 trnpkliie. This section contains the smallest of all 

 Hymenopterous insects, many of which are so minute that 

 they are able to spend their 

 whole larval life within the 

 eggs of other insects, finding in 

 the contents of a single egg 

 sufficient food to last them 

 their lifetime. The insect we 

 select, however, is much larger 

 than this, though it also is a 

 parasite. It is called Gonatopus 

 pedcstris (Fig. 1), and its place 

 here, at the head of the present 

 paper, is a most appropriate 

 one, as it is parasitic upon 

 insects of that gro>ip which 

 yielded most of the illustrations 

 in the former paper. 



If we find in August or 

 September a field in which the herbage has been allowed 

 to grow long and dry, and sweep with a net amongst the 



Fia. 2. — Fore-pai-ts of 



Fig. 1. — Gonatopus pedesfris. 



long grass-stalks, we shall probably cai)ture hundreds of 

 small brownish or yellowish frog-hoppers, Iwlonging 

 chiefly to the two genera Atkysanun and Dellocejjliahi8, 

 the former being the larger of thi> two. Amongst 

 this crowd of jumping creatures, we shall probably 

 notice a few individuals which seem more or less 

 deformed. They are incommoded by having a large black 

 wen-like excrescence growing from some part of the body, 

 generally the fore-parts, and especially at the side of the 

 head, at the junction between it and the thorax (Fig. 2). 

 By this we know that the insect is suffering from the 

 attack of a parasite which is either our GonatopuH, or 

 something akin to it. The black excrescence is, in fact, a 

 sort of case which contains 

 inside it the grub of the 

 parasite. The juices of the 

 host are diverted from their 

 true course to pass through 

 the slender attachment of this 

 black bag to the body, and so 

 to nourish the larva contained 

 within it. 



The case is something like 

 an oval box constructed in 

 two parts, which unite to- 

 gether all round the edge. The Mhysanus obsoUtm, wiih 

 larva within is a footless parasite (a). 

 maggot, which has a very easy 



time of it, being fed entirely at the expense of its host, 

 while it has nothing to do but lie still and enjoy itself. 

 When it is full grown the black skin bursts, the lid 

 coming off as it were, and the imprisoned insect escapes, 

 and soon spins a little cocoon somewhere in the neigh- 

 bourhood. From this cocoon emerges in due time a most 

 odd-looking creature (Fig. 1), something like an ant in 

 general appearance, but with a disproportionately large 

 head, and a most extraordinary pair of fore-legs. A large 

 part of the head is occupied by the huge masses of the 

 compound eyes. The thorax is greatly elongated, chiefly 

 in consequence of the large size of its first segment, the 

 prothorax, which is much more fully developed than is 

 usually the case in this order of insects. There is nothing 

 remarkable about the body, nor about the two hind jjair 

 of legs, save that they are rather long and thin, and that 

 their thighs are clubbed. But it is the fore-legs that 

 constitute the most important part of the creature's 

 anatomy, for upon their skilful manipulation depends the 

 solution of the question whether the insect shall be able 

 to secure for itself a posterity, or whether its line is to 

 become extinct with itself. (Df course, it is the female 

 insect we are referring to throughout. 



To provide forthe deposition of its eggs, it will have to 

 catch a suitable froghopper, aud every entomologist knows 

 that this is one of the most difficult tasks to which ho 

 can be set, for of all insects the froghoppers are the most 

 agile and the most wary ; their awkward habit of suddenly 

 kicking out with their hind legs, and so jerking themselves 

 violently through the air from place to place, makes them 

 the most tantalizing of objects to hunt. To meet the 

 difficulties of the situation, therefore, we find that Gonato- 

 pus is doubly well equipped. In the first place, there are 

 those huge masses of eyes on each side of the head, by 

 which a wide horizon can be scanned, and a good look-out 

 kept for the discovery of a suitable quarry. And then 

 there are the fore-legs, which are a innUniii in parro, and 

 remind one of those household implements which are 

 many tools in one — hammer, screw-driver, pincers, and 

 the like. The leg is not merely a walking machine. It 

 has an extra thick thigh, which means good muscles for 

 the rapid and forceful movement of the whole limb. 



