the Biology of some British Neuroptera. 581 



On other trees it has been found preying upon Oribatids 

 and Bryohia ^^raetiosa K., and it was introduced to one pear 

 tree, infected with the latter, with great success. Two 

 species of Hymenopterous parasites have been bred from 

 C. psociformis. 



Conwentzia pineticola Enderlein. 



Wing expanse 7-8 mm. This species is very similar to the last, 

 though the pigmentation of the wing membrane is sometimes a 

 little darker. It is distinguished from psociformis by the cross-vein 

 in the fore-v/ings, from Rj to Rs, striking the latter on the stem 

 before the fork point. Also the antennae are shorter, averaging 

 thirty joints. 



I am extremely doubtful whether this is a good species, 

 but up to the present have been unable to prove definitely 

 to the contrary. The venational character is very variable ; 

 the number of antennal joints varies, and Enderlein 

 himself quotes one example as having thirty-seven to thirty- 

 eight joints. The male genitalia of the two forms appear 

 to be identical. My own belief is that pineticola is a bio- 

 logical race, or at most a subspecies of C. psociformis. It is 

 not my intention, in the present paper, to deal Vv^ith the 

 systematic side of the Neuroptera, but the following more 

 striking intermediates between psociformis and pineticola 

 are submitted in support of my contention that both are 

 really one. The specimens cited are a few of several in 

 my own collection. 



(1) Wings typically psociformis, antennae 34-jointed, i. e. 

 as pineticola. 1 (^, cocoon taken, London, 30/10/20. 



(2) Wings as psociformis, antennae 32-jointed, i. e. 

 pineticola, 1 sex, cocoon taken, Walthamstow, 9/10/20. 



(3) Left wing as psociformis, right wing intermediate, 

 antennae 34-jointed, i. e. as pineticola, ? sex, data as (2). 



(4) y\%igs intermediate, antennae 35-jointed, ? sex, 

 cocoon taken, London, 30/10/20, same tree as (1). 



(5) Wings intermediate, antennae 37-jointed, 2 $2 and 

 1 (^, Heston Hounslovf, 2/7/21. 



Comventzia jyineticola occurs fairly commonly on plane 

 trees in London. It has also been found on almond, 

 cherry, plum, pear and conifers near London. 



The early stages, eggs and larvae, are not distinguishable 



