104 
Schmitz has bred Ditaenia cinerella from a snail-shell, but as I have 
the same species from flood refuse it is certainly no snail-feeder, 
its presence in the shell being quite occasional. The species seem 
all to hibernate as pupæ, yet Sepedon excepted as Gercke found 
the pupæ of the two species in August, and my pupa of 5. sphegeus 
is likewise from August, developing soon after, but as the imagines 
may be found also early in the year the species have perhaps two 
yearly broods, the second generation then probably hibernates as 
egg or larva; the same may be the case with Hcdroneura rufu as 
my sole pupa of this species was found in September, developing 
in the same month, and it is of course also possible that the other 
species may have two broods in the year, the second brood hibernat- 
ing as pupæ. 
The above remarks hold good for the species I enumerated, with 
the exception of three which as regards their puparia as well as no 
doubt also their feeding habits behave in another and rather interest- 
ing way. These three species are Cdlobacu bifuscicllci and Cteniilus 
pectoralis and punctatus n. sp. When in spring flood refuse at the 
border of fens and lakes is sieved, we find in it plenty of shells 
of small snails of the genera Limnaea and Planorbis, In the shells 
no rest of the snail is present, but a pupa has taken place in them 
(living snails are of course also present). The pupa sometimes is 
found rather deep in the shell so that it is not easily detected. 
The facts are for the rest somewhat difiPerent in the three species, 
so that I shall treat each separately. 
Calobaea bifasciella Fali. The pupa of this elegant little species 
I have found exclusively in Limnaea tmncatula Miill. According to 
the size of the shell the pupa sits more or less deeply inwards, 
sometimes near the opening, and as the puparium fits very closely 
in the shell it looks in the latter case as if the shell was closed 
by a chitinous cover. The puparium is of course placed with the 
anterior end outwards, and it is placed so that the ventral surface 
rests against the outer circumvolution; the anterior half part of the 
dorsal surface lies free in the opening while the posterior half part 
stretches into the shell. The puparium fits so closely in the shell 
that in order to get it out uninjured it is necessary to dissolve the 
Shell with muriatic acid. The puparium is then seen to be of a 
very curious shape, caused by its fitting in the shell. The ventral 
