168 Mr. R. MacLachlan's Monograph of 



Wings uniformly shining fuscous ; neuration blackish, 

 ciliated with golden ; two or three transverse veinlets 

 about the middle of the anterior wings, placed irregularly, 

 and three or four at the base ; pterostigmatical region 

 scarcely darker. 



Abdomen of the male, above, provided at the apex with 

 two incurved and sharply-pointed appendices ; ventral 

 plate large, rounded, obtuse. 



Length of body 2-2| lines ; expanse of wings 6-Q^ 

 lines. 



Common throughout the summer, especially about 

 streams, but also occasionally frequenting standing 

 waters ; generally distributed. 



The larva, described as Branehiotoma spongillm by 

 Westwood, was discovered by Mr. Hogg*, in the sub- 

 stance of SpongiUa Jltoviatilis . It is remarkable from the 

 form of the respiratory filaments, which are placed on the 

 under surface of the abdomen, and, in being articulated, 

 somewhat resemble legs. 



Certain examples of this species are darker than the 

 ordinary specimens, and form WesmaePs nigripennis ; 

 perhaps Burmeister's moHo should also be referred 

 here. 



Rambur would appear to have mistaken the sexes ; 

 his words " Extremite abdominale du male ayant un 

 appendice courbe en haut en forme de crochet," must 

 refer to the ovipositor of the female. 



2. SiSYRA Dalii, MacLachlan. 



Sisyra Dalit, M'Lach. Ent. Mo. Mag. ii. 268 (1866) . 

 Hemerohius nitidulus (Dale), Walk, Brit. Mus. Cat. 

 296 (not of Fab.) . 



Castaneous or pale testaceous, clothed with golden 

 hairs ; antennae dark fuscous, with a pale basal joint. 



Legs pale yellowish, the terminal joint of the tarsi 

 tipped with blackish ; clothed with pale hairs. 



Wings pale testaceous, sub-hyaline, shining ; neura- 

 tion testaceous ; in the anterior icings the transverse 

 veinlets, the axilla of one or two furcations, and a spot 

 on the dorsal margin towards the base, fuscous ; hence 

 these wings have a slightly dotted appearance ; four 

 transverse veinlets in the middle of the wing, two of 

 which are placed in a line, and four others towards the 

 base : posterior ivirtgs paler, the radius and two transverse 

 veinlets blackish. 



