THE ENTOMOLOGIST. 451 
of Matricaria; feeds in the receptacle, and forms a cocoon 
in it.” 
Mecinus collaris, Germ. “From galls on Plantago mari- 
tima; the Hymenoptera (Pteromalus imbutus, Wik.) are 
parasitic on that beetle, and are found in its galls, and form 
a close-fitting case. The smail gnats (Cecidomyia sp ?) 
were also reared out of that plant.” 
One specimen of Tetrastichus Diaphantus, W/k., accom- 
panied the three preceding species: it is, probably, parasitic 
on the Cecidomyia. 
Three species were reared by Mr. Moucreaff from the stem 
of the dock. 1. A little Dipterous fly (Muscide) unknown 
to me. 2. A species of Cynipide. 3. Syntomopus incurvus, 
Wk., probably parasitic on the Dipterous insect. 
“From the willow herb.” The fly much resembles Tetras- 
tichus Adalia, W/k., but the antennz seem to be darker and 
stouter. 
Bracon tenuicornis, Wesm., and Isosoma hyalipennis, W/k., 
from Triticum repens. 
“The galls in the stems of Festuca ovina are of two sorts: 
one single-celled, and containing only one larva; the other 
many-celled, and each cell containing one larva. 
“ Last autumn I separated these as closely as I could, and 
placed each description of galls in close-corked bottles, and 
I felt somewhat confident that by this means I should 
discover the true gall-maker, which 1 fully expected to 
emerge from the single-celled gall. I now send you the flies 
that emerged in May and June.” The flies from the single- 
celled galls are Eurytoma collaris, Wik. The flies from the 
many-celled galls are Eurytoma collaris, Isosoma depressa, 
W1k., Decatoma mellea, Wlk., Pteromalus fulviventris, WI/k., 
and Trigonoderus hirticornis, Wlk.? The Isosoma was the 
most numerous, and next to it the Pteromalus and the 
Decatoma; the Eurytoma was few in number; and of the 
Trigonoderus there were only two specimens. The Ptero- 
malus and the Trigonoderus may be considered to be parasitic 
on the three genera of Eurytomide, and this family, of which, 
among all the Chalcidites, the abdominal structure most 
resembles that of the Cynipide, appear to be occasionally 
gall-makers, and occasionally dwellers in galls made by 
other insects.—Francis Walker. 
