16 A Windfall for the Microscope. 



" brown particles" from the tumbler, observing that a similar 

 change had taken place among them. In less than half an 

 hour numbers of the little larvae had rolled themselves in mud 

 cases (Fig. 10). 



Meanwhile the green particles remained unaltered. On the 

 31st, however, their contents as seen through the microscope 

 seemed to assume a more defined shape. As may be supposed, 

 they were inspected daily with much curiosity. On the 2nd of 

 September the uniform green spots, so often watched, were 

 evidently seen to be exchanged for something moving. It was 

 one of the excitements of a microscope to guess what appear- 

 ance they would have when magnified. 



Fig. 12 represents what the microscope showed when they 

 were conveyed to it, and the form at first sight reminds one of 

 a crayfish, or lobster; but they proved to be the "caddis- 

 worm," larva of the caddis-fly. The immensely long, jointed 

 legs, alike suited for building the well-known habitations of the 

 caddis-worm, and for walking nimbly among water-weeds, and 

 the soft body, evidently requiring defensive armour, were soon 

 recognized. 



I placed them in a glass, stocked with what I believed to be 

 the materials of their trade ; and at first they floated somewhat 

 helplessly on the surface of the water. Ere long, however, 

 these young creatures began very properly to make their 

 clothes; or, as one may say, to build their houses, for theso 

 were real buildings, although no larger than those represented 

 at Fig. 14. The reader may imagine how small the grains of 

 sand must be of which they are constructed. At Fig. 13 these 

 tiny edifices may be seen magnified fifteen diameters. 



The jelly, then, was no other than the eggs of insects, and 

 its appearance corresponded with some descriptions given by 

 Westwood.* He speaks of the eggs of one of the Chironomus 

 family as deposited on the leaves of aquatic plants, and covered 

 with amass of gluten; and he says of the caddis-flies (Phry- 

 ganeidce) that they deposit their eggs in a double gelatinous 

 mass, which is of a green colour, and he adds that the female of 

 Phrygcmea grand/is has been observed to creep down the stems 

 of aquatic plants under the water, for the purpose of placing 

 her eggs in a desirable position. 



The young caddis-worms which emerged on September 2nd 

 were alive and well a fortnight later, and had enlarged their 

 cases considerably. Unfortunately the story ends hero. I was 

 called away from home, locked up the wine-glasses which con- 

 tained the two kinds of larva;, — found them dried up on my 

 return, and was unsuccessful in my attempts for their resus- 

 citation. But I think it will be pronounced that I had 



* Introduction to the Modern Classification of Insects, vol. ii., pp. 62, 51G. 



