1930 ] 
Nesting habits of Prosopis 
175 
family (counting from date of oviposition) and was only 
now completely developed and ready to emerge, the last of 
the series. The hard disc forming the lid of each of the 
cells was in no case broken through, but all the insects had 
bitten out a new channel through the pith and around this 
lid and thus escaped upward into the gallery. The middle 
of April terminated the season of emergence of these bees 
in all the nests which came under my notice. 
MUSCID LARVM TAKEN IN “SCIARA ARMY 
WORM” 
In the spring of 1929 I observed a mass of fungus-gnat 
larvae, usually referred to as a “Sciara army worm” moving 
across a lawn in Chambersburg, Penna. 
With the Sciara larvae and moving along with them were 
two Muscid larvae. When not covered over in the moving 
mass their white bodies were quite conspicuous in contrast 
with the darker color of the Sciara larvae. 
I collected both specimens and the adults emerged on 
July 23rd. They proved to be Muscina pascuorum Mei. as 
determined by Mr. A. B. Champlain of the Penna. Dept, of 
Agriculture, Harrisburg, Pa. Apparently this species has 
not hitherto been reported from Pennsylvania, nor has the 
larva been observed before in America. 
J. R. Stear 
Chambersberg Laboratory 
Penna. Bureau of Plant Industry. 
