170 



PROCEEDINGS ENTOMOLOGICAL SOCIETY 



The fourth larva is that of Hydroscapha natans Lee. and is by 

 far the most interesting of them (figs. 2-13). The species is rep- 

 resented in all stages, from egg to imago. The eggs are in propor- 

 tion remarkably large, oval, smooth, dark brown, without sculp- 

 ture. I observed them first in numbers, attached to the algae 

 with which they were received, and found them afterwards within 

 the female. Only one egg is developed at a time, and this occu- 

 pies nearly one-fourth of the abdomen, (fig. I). A single pupa 

 only was found and this is in too poor condition to describe prop- 

 erly. I give a mere outline of the form in figure II. 



> V -" V S s 

 ^ ... ^ s ^ : 



.air 



frtnoe of ctfta 

 -'ret <x if) t'no at'r 



Sketch, from Life 

 r>u(uT<3.( ~ 



g /-/yc/rosccr/i4a Q~n 



Fig. I. Hydroscapha in natural positions. 



Three larval stages are in the material and evidently no more 

 occur. The first stage is, as is often the case in Coleopterous 

 larvae, somewhat different from the two following, and especially 

 is the pair of peculiar appendices on the eighth abdominal seg- 

 ment (fi, fig. 7) relatively longer than in the two later stages. 

 The full grown larva (figs. 2, 4) is 1.5 mm. long, dark grey, with 

 the anterior and posterior portion of each segment whitish and 

 soft skinned; the number, arrangement, form and length of the 

 seta? and the sensorial punctures on the different parts of the 

 body are shown on the figures (figs. 2, 4). The head is bent 



