August, T8] PARKER: CHLOROPISCA GLABRA HABITS 369 
Historical 
Very little has been written concerning the life history of C. glabra. 
In Europe Kuhn 1 in 1887, found caraway plants attacked by mining 
insects and reared C. glabra from puparia found in the ground below 
the plants. He apparently infers that the larvae mining the leaves 
were of the same species as the puparia taken from the soil. Several 
notes on the larval habits of Chlorops assimilis Macq. now considered 
a synonym of C. glabra, are given by Coquillett 2 as follows: “On July 
26, 1884, Mr. Theo Pergande found two larvae and one puparium of 
this insect among a colony of aphids on the roots of Poa pratensis. One 
of the flies issued on the 31st of the same month.” “On September 6, 
1892, several sugar-beets were received from the W. B. Sugar Company, 
of Castroville, California, and in the leaves were found a number of 
the puparia of this insect. The adult flies issued two days later. 7 ’ 
‘ ‘Larvae and puparia of this species were taken September 1, 1897, by 
Messrs. F. H. Chittenden and F. C. Pratt in the earth about the roots 
of horse radish in the vicinity of Tennallytown, D. C. Several adults 
issued a few days later.” 
To Professor J. M. Aldrich, who is making an extensive study of the 
Oscinidae (Chloropidae), I am indebted for the statement that while C. 
glabra is a very abundant species throughout this country and occurs 
in Europe, Africa and South America, little is known concerning its life 
history. 
In the fall of 1908 Professor R. A. Cooley found puparia of a dipteron 
in sugar-beet root-louse colonies at Bozeman and he suggested in the 
original record note that it might be an enemy of the root louse. 
Adults emerged the following spring and were identified by Coquillett 
as Chlorops assimilis Macq. (C. glabra). 
Throughout the study of the sugar-beet root louse which was under¬ 
taken as an Adams project in 1909, larvae and puparia of C. glabra 
were found in abundance during the late summer and fall in root-louse 
colonies and it was suspected from the beginning that it was predaceous 
upon the root lice. In hundreds of field observations, however, we 
were never able to actually see the larvae attack living lice nor feed upon 
dead lice and as no other member of the Oscinidae was known to be 
predaceous, we hesitated to class it as a root-louse destroyer without 
more definite knowledge. In 1916 a detailed study of C. glabra was 
undertaken, 3 * * the results of which are embodied in this paper. 
1 Kuhn, Julius. Separat Beiblatt des Berliner Tageblatt, No. 9, p. 265, 1887. 
2 Coquillett, D. F. On the habits of the Oscinidae and Agromyzidae reared at the 
United States Department of Agriculture—Division of Entomology. Bui. 10, new 
series, p. 70-72, 1898. 
3 Mr. A. L. Strand, a careful student assistant, was in charge of the rearing experi¬ 
ments. He devised the improved rearing cage and made many of the observations 
recorded in this paper. 
