160 HEMEROBtJDJE. SIALID^E. 



larva has attained its full growth, and is ready to assume the 

 pupa state, it spins a perfectly round cocoon of a silky matter, 

 the exterior of which it covers with sand ; and from this the 

 perfect insect makes its escape at the end of fifteen or twenty 

 days. None of this group are found in Britain. 



743. The family HEMEROBIID^E, which is closely allied to 

 the preceding, but readily distinguished therefrom by its thread- 

 shaped antennae, is remarkable for the exceeding brilliancy of the 

 eyes in most of the species, and for the delicate structure and 

 varied colour of the wings. The eyes often resemble the most 

 highly-polished gold ; and the wings frequently reflect the 

 prismatic colours ; so that, although of small size, these insects 

 are very conspicuous. They are for the most part inhabitants 

 of temperate climates ; and many species abound in Britain. 

 They usually fly during the twilight, remaining inactive during 

 the day ; and they emit a very disagreeable odour when handled. 

 The females deposit their eggs upon plants, attaching them at 

 the extremity of a long slender footstalk, the base of which is 

 fastened to the leaf ; this footstalk is composed of a white viscid 

 matter, discharged by the female at the time of laying her egg, 

 and speedily hardening by exposure to the air. The eggs, thus 

 curiously fixed in small clusters, have the appearance of minute 

 fungi. The larvae are extremely voracious, and especially attack 

 the Aphides ; unlike the Ant-lions, however, these Aphis-lions 

 (as they have been termed) do not remain concealed in one spot, 

 but wander in search of their prey where it is to be found in 

 the greatest abundance. So ravenous are they, that they do 

 not require more than half a minute to suck the juices from one 

 of the largest Aphides ; and they not unfrequently attack each 

 other, the conqueror in like manner sucking the body of the 

 vanquished. During the summer they arrive at their full 

 growth in about fifteen days ; they then spin a silken cocoon, in 

 which they remain as inactive pupaa during the winter; and 

 come forth in the succeeding summer. 



744. The remaining families of this Order may be very 

 briefly noticed. The SIALID,E are a small group of moderate or 

 large-sized Neuroptera, having very large anterior wings. They 



