1866.] 269 



of several (3 to 5) trausvcrse veins placed irregularly rather before the 

 middle, which transverse veins, with others placed nearer the base, are 

 distinctly darker ; a peculiarity shared also by the small marginal and 

 other furcations, especially at the points where the veins divide, hence 

 the wings appear slightly spotted. Infuscata there is very rarely more 

 than one transverse vein in the middle of the wing, and in terminalis 

 these veins are almost entirely absent ; the former is also at once sepa- 

 rable by its universally darker colour, and the latter by its great 

 pallidity, and by the pale tips of the antennae. 



This species has been found by Mr. Dale at Grianville's Wootton, 

 and also at Ambleside. It appears to be unknown on the Continent. 



2.—IIemerobius pellucidus, (Dale) Walker, Brit. Mus. Cat, Neurop., 

 pt. 2, p. 284, 19 (1853). 



Semerobius fuscescens, Wallengren, Ofversigt af Kongl. Vetens- 

 kaps-Akademiens Forhandlingar, 1863 (published in 1864), p, 22, 10. 



This little species is of the same size as S. elegans, Steph. (== -H". 

 Marshami, Steph., = Mucropalpus pygmcBus, Eambur), which at first sight 

 it greatly resembles. A closer examination will show, however, that in 

 H. elegans the longitudinal veins in the anterior wings are delicately 

 spotted with white, of which there is no trace in pellucidus ; but there 

 is a more important structural difference in the neuration, for H. elegans 

 possesses only two sectores radii, whereas in pellucidus there are three. 

 The transverse veins are somewhat clouded, but otherwise the wings are 

 remarkably pellucid ; in elegans the anterior wings are more or less 

 clouded and spotted with grey. 



According to "Wallengren's description I have no doubt whatever 

 t\ioX \\\& fuscescens is identical viit]x pellucidus ; for the comparison he 

 draws between pygmceus (elegans) and fuscescens answers precisely to 

 our insect. He says that it is found here and there on pine trees. 



Mr. Dale tells me that pellucidus is found at Grianville's Woot- 

 ton, Dorsetshire, but was more common formerly than at present. 



3. — Hemerobius dipterus, Burmeiater, Handb. Ent. 2, p. 973, 1 ; Curtis 

 Trans Ent. Soc. London, new series, vol. 3, p. 56. 



This most singular insect may at once be known by the almost en- 

 tire absence of posterior wings, these organs being reduced to two 

 minute lobes. As I have not the specimen before me at the present 

 moment, 1 cannot give a detailed description here. One singular charac- 

 ter may be worthy of notice, viz., that the anterior wings are so formed, 

 that above they present a very convex surface, and correspondingly 

 concave beneath. 



