LARVAL CONDITIONS 77 



it is undergoing a gradual metamorphosis, and, like 

 the Perlidse, at no time does it assume the real 

 pupal condition that is, the dormant chrysalis stage 

 common to the Trichoptera, Sialidse, and the 

 Diptera. 



It should therefore, strictly speaking, only be alluded 

 to as being in a larval condition until it becomes a sub- 

 imago, but for distinction the latter period of its larval 

 condition may be termed pupal. It is at about this 

 latter period that it begins to be of most interest to the 

 fly fisherman, and, with the kind assistance of Mr. 

 Chas. 0. Waterhouse, of the South Kensington Museum, 

 I have been able in Plate XIV., Figs. 1 and 2, to give 

 two characteristic views of its appearance just before 

 the sub-imago state. The beautiful illustrations on 

 Plates XIV. and XV. were drawn for me by Mr. Horace 

 Knight, of the Natural History Museum. Fig. 1, 

 Plate XIV., shows the pupal stage of the larva of the 

 May -fly, Ephemera vulgata, twice its natural size. 

 Fig. 2 represents the pupal stage of the larva of 

 Cloeon rufulum, a fly resembling the Red Quill. The 

 larval period of the different Ephemeridae lasts from 

 one to two years. 



There are several varieties of the larvae, correspond- 

 ing to the several kinds of Ephemeridas, and in each the 

 appearance and the habits differ some crawl, some 

 burrow, and others, again, swim but in all the varieties 

 their larval appearance alters as they attain full size, 

 and beneath the transparent integument covering their 

 bodies can be discerned the gradual development of 



