NATURAL SCIENCES OP PHILADELPHIA. 241 



vein ; the fifth at the tip of the upper branch of the radial vein. The first 

 three longitudinal veins and the base of the others are pale. 



Compared 13 specimens (^ and 9 ) 



Virginia, Trenton Falls, etc., (nob.) June, July. 



This species is very easy to recognize by the cross-vein which divides the 

 second radial area in two sections. 



11th Section. 



Wings without petiolated areolet, somewhat like Meig. i. tab. v. f. 4. 

 This group is purely artificial and comprises two species which have the 

 above character in common. 



L. quadrat a. Cinerea, antennis palpisque fuscis, pedibus pallide ferru- 

 gineis, femorum, tibiarum tarsorumque apicibus fuscis, alis subhyalinis ; long, 

 lin. 2-3|. 



Front and vertex greenish cinereous ; palpi and antennae brown ; basal joints 

 of the flagellum a little paler ; verticils long. Thorax cinereous ; praescutum 

 yellowish cinereous without distinct stripes ; pleurae slightly hoary ; halteres 

 pale ; feet yellowish ferruginous ; coxae and base of femora pale yellow ; tips 

 of femora, tibiae and tarsi brown. Abdomen brownish ; genitals yellow. 

 Wings slightly infuscated, pale at the root ; stigma pale ; veins brown ; sub- 

 costal and mediastinal veins pale yellow ; the mediastinal cross- vein is near 

 the tip of the mediastinal vein ; the stigmatical cross-vein is immediately be- 

 yond the origin of the radial fork ; the central cross-veins form a nearly 

 straight line. 



Ten (J* 9 specimens. Virginia, Maryland, in May and June (nob.) 



L. lent a. Pallide silacea, antennarum flagello palpisque infuscatis, fronte 

 canescente, alis hyalinis, stigmate pallide infuscato ; antennae maris dnse 

 pubescentes ; long. 2f 3^. 



Pale ochraceous yellow ; palpi and antennae (excepting the basal joints) 

 fuscous ; antennae of the ^ thickly covered with a short pubescence ; verticils 

 in both sexes short; joints oval: last joint small, club-shaped; front hoary; 

 vertex infuscated ; tip of the tarsi infuscated. The falciform appendages of 

 the (5* forceps are more diverging in this species than in the others of the 

 genus. Wings pale yellowish ; costal, mediastinal, subcostal and pobrachial 

 veins yellow ; the others brown ; stigma slightly infuscated round the cross- 

 vein, which is situated near the origin of the radial fork (a little before or a 

 little beyond it, its position differing sometimes on both wings of the same- 

 specimens) ; mediastinal cross-vein near the tip of the mediastinal vein. 



The general appearance of this species is very much like that of L. a r e o- 

 1 a t a, but it is easy to distinguish the former by the absence of the petiolated 

 areolet, the shorter discal areolet, etc. 



Compared ten $ 9 specimens. Virginia, Maryland, D. C, May, June 

 (nob.) Illinois (Mr. Kennicott.) 



11th Section. 



Wings covered with a fine pubescence on the whole surface; no petiolated 

 areolet ; neuration like Meig. vol. i. tab. v. f. 4, but second radial area nearly 

 as long as the lower one ; antenna, icith apparently 17-joints; palpi short. 



The location of this group within the present genus is only temporary ; the 

 pubescence of the wings and the number of joints of the antennae would seem 

 to justify its separation ; but having only a single specimen in my possession, 

 I have not been able to come to any definite conclusion as to its position in 

 the system. 



L. pilosella. Pallide fusca ; antennis, palpis et fronte fuscis ; tergo et 



1859.] 18 



