138 MAINE AGRICULTUR.XU ExPERTMEXT STATION. I912. 



48. Sciara occllaris Comstock. 



Rept. of Comm. of Agr. 203. 1882. 



Male. Length 1.5 mm. Head black, antennae dark brown, 

 basal joint light yellowish brown ; pronotum light yellowish- 

 brown ; mesonotum yellowish brown in the center and darker at 

 the edges ; scutellum dusky brown : metathorax dark brown, 

 almost black ; abdomen with caudal portion of the segments, 

 blackish, cephalic portions yellowish brown ; clasper lighter 

 brown. Poisers, with knob blackish, and base light brown. 

 Tibiae and tarsi dusky brown ; femora lighter ; coxae still lighter. 

 "N. Y., D. C." The figure given by the author of the wing 

 shows that this species is closely related to S. coprophila. 



An examination of the cotype material from the Cornell 

 University collection shows that in structural characters includ- 

 ing antennas and wing venation the species is closely related to 

 5. coprophila from which it differs in color characters and in the 

 structure of the clasper which has on the dorsal-mesal margin 

 2 or 3 strong setae in addition to the apical setae (Fig. 263). 

 This species was formerly supposed to cause the ocellate spots 

 on maple leaves which are now attributed to a Cecidomyiid. 

 Specimens from Buffalo, and Lancaster, N. Y., collected by 

 Mr. M. C. XdiU Duzee do not diff'er from tlie types (Fig. 265). 



The following descriptions by Say (Complete Writings I. II). Walker 

 (List. Dipt. Brit. Mus. I) and Fitch (Second Rept. 484-487) are too 

 brief and general to permit of a recognition of the species. The dimen- 

 sions given have all been reduced to the metric system. 



S. abbreviata Walker. "Length 2 mm. Body black; abdomen tawny; 

 feelers piceous ; thighs tawny; shanks and feet brown; wings colorless; 

 veins pale brown ; poisers tawny. Canada ; N. J.. N. H." 



S. atrata Say. "Length less than 5 mm. Entirely deep black, polished, 

 immaculate; wings dusky, iridescent; nervures dark fuscous; poisers 

 black ; thorax in a particular light somewhat pruinose ; abdomen opaque, 

 with short black hairs ; spines of the tibia rather longer than the trans- 

 verse diameter of the tibia. 'X. W. Terr.' The nervures of the wings 

 agree with those of S. Tlwniac." S. thoniae has a venation of the type 

 of S. picea but Ri ends about opposite the forking of the media. 



S. dimidiata Say. "Female. Length less than 5 mm. Thorax pol- 

 ished; wings fuliginous; costal margin blackish; middle nervure very 

 distinct ; poisers blackish ; abdomen dull fulvous, with a few blackish 

 hairs on the 3 basal joints, fourth a little darker; tip black; feet piceous 

 black. Louisiana." 



