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to superficially resemble a simple form of compound eye on each 

 side. The thoracic legs have a small and very sharp claw, which 

 is abruptly bent backvN^ards. Segmentation is deep and conspicu^ 

 ous, the cuticle corrugated and in life more or less thickly cov- 

 ered with a floury efflorescence. The third, fourth, fifth and 

 sixth abdominal segments bear very short prolegs, which, how- 

 ever, are capable of further protrusion than is usually observed 

 in preserved specimens. Thev are furnished with a regular cir- 

 clet of hooks to the number of about 20 in large and 12 or 14 

 in smaller larvae. An additional terminal pair of legs or clasp- 

 ers very closely approximated, are imperfect, being armed 

 with hooks only along the front side. In some species of 

 Hctcropsyche the hooks are much more numerous, 40 or 50 to 

 each proleg. 



One or more larvae may be seen on a single hopper, but, in 

 some cases at least, it appears that only one of these is able to 

 become mature. The moults take place on the hoppers' back, 

 and one or more cast skins were frequently noticed thereon. Li 

 the case of Agaiuopsyclic the caterpillars were found only on 

 mature Delphacids. They affect both short and long winged 

 forms alike, and either sex of the hopper. In most cases at least 

 the parasite (unless resting or moulting) has the head turned 

 towards the tip of the abdomen of the host. Although in many 

 of the hoppers, that were found affected, there is no waxv excre- 

 tion, such as the parasitic caterpillars have been supposed to feed 

 on, yet it is probable that these feed largely on the sweet liquid 

 excretion or honey-dew, which is abundantly produced at all 

 times. This opens up the question as to whether the parasite is 

 or is not fatal to the host. Koebele from observations made at 

 Sydney believed that the hoppers died soon after the parasite 

 quitted them. In some cases at least with Aganwpsychc at 

 Cairns, death followed quickly on the withdrawal of the full- 

 fed caterpillar. Even immediately after this event in some speci- 

 mens of a Delphacid, a collapse or distortion of the dorsal 

 sclerites of the abdomen was obvious, and healthy hoppers in- 

 cluded in the same jar as parasitized ones outlived the latter. It 

 would however be premature to say that a mature hopper bear- 

 ing these parasites is incapable of laying fertile eggs. In the case 

 of species other than Againopsychc, the caterpillars were observ- 

 ed on nymphs as well as on mature hoppers. Should the nymphs 

 moult, it would appear probable that the parasitic caterpillar 

 would be also discarded, but it is quite possible that the drain on 

 the strength of the host is sufficient to prevent moulting, as is 



