148 
T^E ENTOMOLOGIST’S WEEKLY INTELLIGENCER. 
Argynnis Lathouia, 
Vanessa Antiopa. 
As I have but a few specimens to spare, 
gentlemen will please to write first. My 
specimens are in fine condition, and I 
expect such in return. — Rev. G. C. 
Green, Modbury Vicarage, Ivy bridge, 
Devon; August 3. 
Xanthia Gilvago. — There is a mistake 
in my notice of “ Exchange ” in last 
week’s ‘Intelligencer’ (p. 140) : Xanthia 
Cilrago should have been Xanthia Gil- 
vago. I am sorry the error should have 
occurred, as I am afraid gentlemen will 
think me very extortionate in my re- 
quirements. — Joseph Wragg, 7, Spring 
Gardens, Doncaster ; August 3. 
Exchange . — Having a few good speci- 
mens I shall be glad to receive ofiers 
from any gentleman in want of — 
Acidalia Marginepunctata, 
... Emutaria, 
Abraxas Ulmata, 
Crambus Pinetellus, 
Polyommatus JEgon, 
Coenonympha Davus. 
Parties not hearing from me in six days 
may conclude their oflfers are not ac- 
cepted. — Edwin Miller, 28, Back 
George's Road, Manchester ; July 31. 
Exchange. — Larvae of Notodonta 
Ziczac. — E. Tearle, Gainsborough ; 
August 2. 
ON PHRYGANID.® AND THEIR 
PARASITES. 
BY DR. HAGEN. 
Science has to thank Mr. Walker for 
one of the most interesting discoveries, 
in the observation that Hymenoptera 
{Agriolypus armatus) go under water in 
order to deposit their eggs in the larvae 
of Phryganidas. It seems very extra- 
ordinary that creatures whieh appear 
only adapted to live in the air should 
be capable of remaining under water for 
some time in order to execute certain 
operations. 
It had been already previously ob- 
served that Phryganea grandis goes under 
water in order to lay its eggs, and sub- 
sequently this observation was repeated 
amongst the Agrionidae, in Lestes, for 
instance. Here the male is so polite as 
to accompany the female under water. 
The process of respiration is, however, 
assisted during the short period neces- 
sary by the layer of air on the abdomen 
which the insect takes under water with 
it. It has also been long known that 
some Diptera are parasitic in the larvae 
of Phryganidae, but I am not aware that 
the species are known. 
Some species of Phryganidae, espe- 
cially Silo pallipes (which is not scarce 
in May in hedges near Lewisham) are 
much infested with the parasitic Agrio- 
lypus. Von Siebold has made a very 
interesting discovery respecting these in- 
sects ; namely, that the larva of a Phry- 
ganideous insect, which is infested by a 
parasite, before changing to a pupa, spins 
a long firm thread by which it attaches 
its case : we can only consider this gift 
of spinning as a morbid craving — a spe- 
cies of excitement caused by the parasites 
within. According to Von Siebold’s ob- 
servations, the cases which contain para- 
sites are always fastened by a thread, 
whilst all others are without a thread. 
