288 INSECTS AT HOME. 



order, we will proceed tj a more detailed examination, and 

 take for ovir type the Gueat Caddis-fly (Fhryganea grandis), 

 which is drawn on Plate VIII. Fig. 7, and can be easily 

 recognised from the figure. 



In this genus the spurs of the tibise are moderately 

 developed, and the wings are very heavy. The palpi of the 

 male have only four joints, whereas those of the female have 

 five. The wings are very thickly covered with hair, so thickly 

 indeed that, under the microscope, they look as if they were 

 clothed with fiu'. The hairs are comparatively pale and small 

 on the membrane of the wing, but dark, stout, and bristle- 

 like upon the nervures. The body is similarly furred, and 

 even the antennae are so densely haired that the divisions of 

 the joints are quite hidden. It is on account of this profuse 

 growth of hair that the name Trichoptera, or Hairy-wings, 

 has been given to this order of insect. 



There is no particular beauty of colour to be found in any 

 of the Trichoptera, the hues being in all the species nothing 

 more than various shades of brown, the difference in colour 

 being produced in most species by the greater or less admixture 

 of yellow. 



The habits of these insects are very interesting. Unlike the 

 Lacewing-fly, they are quick on foot, and can run with a 

 curious celerity, being even able to make their way upon the 

 surface of the water, over which they scuttle , quickly, using 

 much exertion, and the edges of their closed lower wings 

 leaving a long track behind them. They can even travel 

 under water. The females are in the habit of crawling 

 down the stems of aquatic plants nearly a foot below the 

 surface, in order to deposit their eggs. If the plant to which 

 they are clinging be smartly tapped, they will at once leave it 

 and swim under water to another submerged plant. This 

 habit of theirs often causes them to fall victims to various fish, 

 which towards midsummer find an unfailing supply of such 

 food. 



As in the case with the Stone-flies, which have already been 

 described, the female Caddis-fly collects her eggs and carries 

 them about at the extremity of the body. The egg-cluster is 

 double, green in colour, and the eggs are held together by a 

 gelatinous substance, in which they are enveloped. By means 



