54 Psyche [April 



fourth vein 6 times as long as penultimate section; veins 3 and 4 

 gradually divergent on their last sections; last section of fifth vein 

 about one third longer than penultimate section. Length, 2 mm. 



Type, Monticello, 111., June 28, 1914 (J. R. Malloch). Taken 

 by sweeping vegetation on bank of Sangamon River. Food plant 

 unknown. 



This species will "run down" to section 34 in the table referred to 

 previously, but may be separated from both of the species therein 

 by the comparative lengths of the last 2 sections of fifth vein as 

 well as other characters. Both isolata Malloch and fragarice 

 Malloch have the last section of the fifth vein shorter than the 

 penultimate section. 



A NEW SPECIES OF THRIPOCTENUS (Chalcidoidea).i 

 By L. T. Williams. 



During an afternoon's collecting in a swampy spot near the Ar- 

 nold Arboretum, Forest Hills, Mass., a few gaUs on willow twigs 

 were secured and brought into the laboratory at the Bussey In- 

 stitution. A casual examination on the date of their collection 

 (July 22, 1915) showed that they contained immature insects of 

 some sort, but no further attention was paid them until August 

 10, when the galls were opened and found to contain several large 

 black thrips, and a single minute Chalcidoid parasite. Any 

 possible doubt as to the relationship between the insects was 

 removed when the parasite was identified by Professor Brues as 

 belonging to the genus Thripoctenns, which is known to be an 

 enemy of the Thysanoptera. 



The genus Thripoctemis was proposed in 1911 by Crawford for 

 a new species from California, belonging to the sub-family Tetras- 

 tichinse, and described by him under the specific name of russelli 

 in honor of its discoverer, the late Mr. H. M. Russell. A second 

 species has recently been described in Europe by Vuillet. I have 

 not had access to this description but the differences in habitat 

 and in the systematic positions of the hosts would indicate that the 

 present species is perfectly distinct. The characters distinguishing 

 it from the type species are well marked, as will be noted later. 



I Contributions from the Entomological Laboratory of the Bussey Institution, Harvard 

 University, No. 112. 



