HYDKOCAMPA NYMPBJEATA. 101 



on it just as 1 have described above, and by the 18th 

 of the month the water was crowded with tiny cases 

 not one-eighth of an inch long. 



After moulting the black colour of the head of the 

 larva became brownish-ochreous, the collar-plate still 

 black ; the body dirty whitish with broad greenish 

 dorsal vessel ; and by the help of a strong lens I could 

 see the fine opaque whitish tracheal thread. The larvae 

 continued to thrive and were frequently making fresh 

 cases, half at a time, until the period arrived for 

 hibernation, when the cases were spun up flat against 

 the leaves, and, content with what 1 had learnt, I sent 

 them adrift to take their chance in a state of freedom. 

 (William Buckler, 3rd March, 1881 ; E.M.M., April, 

 1881, XVII, 249—254.) 



Hydrocampa stagnata. 

 Plate CLII, fig. 1. 



When I was investigating the early stages of the 

 other species of Hydrocampidde with aquatic larvas, I 

 had been foiled with Hydrocampa stagimta, but, in the 

 early summer of 1876, 1 was fortunate enough to find 

 a kind and enthusiastic helper in Mr. W. R. Jeffrey, 

 of Ashford, and by the aid he rendered me I am now 

 able to give a full account of this species throughout. 



In Staiuton's Manual, the larva is counted among 

 the unknowns ; Guenee says nothing about it ; but 

 from the synonymy of the species dootamogalis Hb. 

 being one of its names in Staudinger aud Wocke's 

 Catalogue) it would appear that Potamogeton had 

 passed for its food, and Dr. E. Hofmann says that 0. 

 Hofmann found it in cases made of the leaves of that 

 plant. But this notion had been driven out of my 

 head by the result of many attempts to find the larva 

 in such a situation, a,nd I had come to suspect that 

 Sparganium would prove to be the right food, a 



