1854.] WESTWOOD — FOSSIL INSECTS. 381 



in PL XVII . fig. 20. Two slabs, containing the fossil and its cast, were 

 found, but unfortunately the surface of the stone is in both so much 

 abraded that the precise form of the " cells " cannot be determined. 

 This, together with the fact of only one pair of wings, apparently the 

 anterior, being preserved, will prevent its relations being determined, 

 as the form of the anal angle of the several wings (unfortunately lost 

 m the specimen before me), and other minute characters presented in 

 the structure of the head, eyes, and ocelli, are the chief characters 

 adopted for generic distinction in this family. 



The discovery of this and many other fine fossil wings of Di-agon- 

 flies, in the Lias, Oolite, and Purbeck formations, is interesting in 

 several respects, both geological and zoological. Their presence in 

 the winged state in a form so identical with those of the existing races 

 of these insects, implies, of course, an abundance of winged, and, for 

 the most part, herbivorous insects ; whilst the aquatic condition of 

 their larvse implies a condition of the water identical with that which 

 is now m existence, as it must have been similarly acted upon chemi- 

 cally by the curious respiratory apparatus of these larvse. Moreover, 

 whilst the remarkable fact obtains in the present physical condition of 

 the insect world, that many of the largest aquatic insects occur in 

 temperate climates (the gigantic Nepidce. forming the only exception), 

 we find only amongst these fossil insects traces of the Libellulidce, 

 the great Water-beetles of the families Dyticidce and HydrophilidcB 

 never appearing, as far as hitherto ascertained, amongst these fossil 

 remains. 



III. Supposed Insect from the Lias. PI. XVIII. fig. 2, 



In PL XVIII. fig. 2 is represented a dark-coloured obscure object, 

 about ^ inch, long, which was found in the Lias by the Rev. P. B. 

 Brodie. This exhibits a triangular space in front, which has the ap- 

 pearance of a scutellum together with the closed wing-covers of one 

 of the Pentatomid(B. It is preceded by a small dark space, which 

 may represent the advanced pronotum ; but I dare not pronounce 

 upon its character with any attempt at precision. 



IV. Insect Remains from the Corfe Clay*. 

 PL XVI. figs. 34, 35. 



Four small slabs of white tertiary clay, from the Leaf-beds at 

 Creech, near Corfe and Wareham, have been forwarded to me by 

 the Rev. P. B. Brodie, from the collection of W. R. Brodie, Esq., 

 of Swanage. Each little slab contains an elytron of a distinct species 

 of Beetle. 



The most characteristic, represented in PL XVI. fig. 34, is 4 lines 

 long ; very narrow ; flattened, and gradually attenuated to the tip ; 

 with eight distinct, punctated, longitudinal striae, and a short one 

 near the base of the suture. This was probably the elytron of some 

 narrow beetle allied to Ayrilus, amongst the Buprestidce. 



The second elytron is 6 lines long ; of nearly equal width for two- 



* These specimens were noticed in Quart. Journ. Geol. Soc. vol. ix. p. 51. 



