76 Bulletin of the Brooklyn Entomological Society Vol.X 



There is no record of gall midges inhabiting pine seeds or 

 cones, though it would not be surprising if such were discovered 

 in the near future, since Dasyncura canadensis Felt has been 

 reared from the seeds of spruce. 



TWO NEW SPECIES OF LIOTHRIPS (THYSANOPTERA). 



By J. Douglas Hood, U. S. Biological Survey. 



Both species described below are from eastern United States, 

 and are made known in a preliminary way at this time in order 

 that the name of one of them — an exclusive feeder on chestnut — 

 may be used in connection with the study of the chestnut blight 

 disease. Part of the material from which this species is described 

 was kindly transmitted for determination by Dr. A. D. Hopkins, 

 forest entomologist of the U. S. Bureau of Entomology. 



Xiothrips castaneae sp. nov. (The Chestnut Leaf Thrips.) 



Female (macropterous) . — Length about 1.7 mm. Color dark blackish 

 brown or black; antennal segments 3 and 4 and base of 5, yellow; fore 

 wings with brown median streak in basal half. 



Head about 1.2 times as long as wide, broadest slightl}^ behind eyes, 

 •cheeks gently arched, slightly convergent posteriorly; vertex roundly 

 produced in front of eyes, the anterior ocellus overhanging the insertion 

 'of antennae; dorsal and lateral surfaces deeply and closely roughened with 

 transverse lines and set with several short spines ; postocular bristles nearly 

 as long as eyes, blunt but not expanded at apex. Eyes nearly one third as 

 long as head, not protruding. Posterior ocelli exactly opposite the poste- 

 rior margin of anterior fourth of eyes. Antennae 1.9 times as long as head, 

 of the general form and structure common to the species of the genus ; 

 sense cones small, formula: 3, o-i ; 4, 1-2; 5, i-i""^; 6, i-i""^; 7 with i on 

 dorsum near apex; color of antennae: segments i and 2 nearly concolorous 

 with head, 2 yellowish apically ; 3 and 4 nearly clear lemon yellow, 4 some- 

 times very slightly infuscate apically; 5 with at least the pedicel lemon 

 yellow, becoming blackish brown at apex ; 6-8 blackish brown, concolorous 

 with I and 2. Mouth cone subacute, attaining or slightly surpassing base 

 of posternum. 



Prothorax about 0.51 as long as head and (inclusive of coxae) nearly 2.6 

 times as wide as median dorsal length ; all bristles present, blunt but not 

 expanded at apex, the midlateral pair usually subequal in length to the 

 postoculars, the two pairs on the anterior margin subequal but slightly 



