236 Mr. R. M'Lachlan's Descriptions of the 



determine with certainty the particular species intended by almost, 

 if not quite, all of these authors, must be an impossibility. In 

 those that I have had an opportunity of consulting, it is difficult 

 to fix even the generic position of the insect described. Of the 

 two figures referred to, that of Reaumur (Memoires des Insectes, 

 vol. 3, tab. 13, fig. 8, 9, 11) would seem to be a Limnephiliis of 

 the sub-genus Grammotaulivs, and that of Schaffer (Icones In- 

 sectorum circa Ratisbonam, tab. 1C8, fig. 2, 3) may be a Desmo- 

 taulius or Anabolia. Kolenati copies these references almost 

 verbatim in describing his striatus, which^ from an examination of 

 the types, proves to be distinct from Pictet's. 



S. lateralis, Steph. (PI. IX. fig. 4.) 



Halesus lateralis, Stephens, 111. p. 210, 6 ; Halesus latipennis, 

 Stephens, 111. p. 209, 4 ; Liwnephilus tenehrosus, Curt. Coll. 



The anterior wings are broader and more rounded at the apex 

 than in the last three species. 



Antennae and head reddish-ochreous ; thorax grey, black at the 

 sides ; abdomen greyish-ochreous ; legs greyish-ochreous, with 

 black spurs and spines ; anterior wings dark reddish-grey, the pale 

 spots smaller and less numerous than in the three last species ; 

 margins scarcely paler, with spots and clouds of the ground colour ; 

 a spot at the thyridium, and one or two spots (not always present) 

 at the base of some of the apical cells, conspicuously paler in con- 

 sequence of the dark ground colour ; occasionally the ground 

 colour is broken up into numerous small spots, in which case the 

 wings assume an irrorated appearance ; posterior wings sub- 

 hyaline, rather smoky, the apex yellowish. 



Upper margin of last abdominal segment produced into a 

 tongue-shaped process (similar to the last species), which is bent 

 under and thickly set with short black set£3e ; appendices superiores 

 small, rounded, the tips only visible ; appendices inferiores broad 

 at the base, with a prolongation upwards, obtusely pointed ; lower 

 sheaths curved inwards, parallel at the tips. 



Long. Corp. 6 — 8 lin. ; exp. alar. 17 — 18 lin. 



Not very common in the neighbourhood of London, appears in 

 June and continues for some months ; also in Devonshire, Hertford, 

 New Forest, &c. 



The form of the upper margin of the last abdominal segment is 

 very similar to the last species, but this species may be readily 

 separated by its larger size, the rounded apex of the wings and by 

 the form of the inferior appendages. In Stephens's collection the 

 types of his lateralis and latipennis were labelled by Dr. Ilagen 



