NO. 2119. BRITISH FOSSIL INSECTS— COCKERELL. 471 



not otherwise known. Since the figures are small and not very 



detailed, and the specimens themselves were never very critically 



studied, it is clear that our Imowledge of the subject is much less 



than the long array of generic and specific names would suggest. Of 



the 49 Mesozoic Blattoids, 27 were described and named by Scudder 



in 1886. 



Tertiary (42 species). 



Coleoptera. — Two from Corfe (? Middle Eocene), named by Giebel 

 in 1856; one from Bovey Tracey (Upper Eocene), named by Heer in 

 1862; one from Mundesley (Upper PUocene), named by Curtis in 

 1840. 



Isoptera. — ^Three species of Mastotermes described by v. Rosen, two 

 from Gurnet Bay (Oligocene), and one from Bournemouth (Eocene). 



Lepid-optera. — Lithopsyche antiqua Butler, "from Gurnet Bay. 



Odonata. — One from Gurnet Bay, described below. 



Diptera. — Nineteen from Gurnet Bay, described below. 



Hymenoptera. — Ten from Gurnet Bay, described below. 



Homoptera. — Four from Gurnet Bay; three described below, and 

 one by Woodward in 1879. 



Post Tertiary (8 species). 



Eight species of Coleoptera, all living species, have been recorded. 

 The total number of British fossil, insects to date is accordingly 368 

 species, of which 44 are first described in this paper. Undoubtedly 

 many others have been collected and await description. Brodie, in 

 Geological Magazine, December, 1893, pages 538-540, and 1894, 

 pages 167-169, refers to large undescribed collections from Gurnet 

 Bay. These are now in the British Museum, and I hope to have an 

 opportunity to describe them during the coming year. 



DESCRIPTIONS OF GENERA AND SPECIES. 

 LIAS INSECTS. 



The insect-fauna of the British Lias (lowest division of the Juras- 

 sic), as far as we know it, consists of medium sized or small species, 

 the Coleoptera and Orthoptera being most abundant. Diptera, 

 Lepidoptera, and Hymenoptera were apparently absent. The Cole- 

 optera have the most modern facies, and although they doubtless aU 

 belong to extinct genera, several of the modern families were appar- 

 ently aheady in existence. Still more remarkable is the appearance 

 in several species of elytral stripes, representing the same fundamental 

 pattern as we see in living beetles. The Blattoid forms, which are so 

 conspicuous in the Paleozoic, seem to be relatively scarce and insig- 

 nificant in the Lias; but later, in the Oolite, they abound. The 

 Odonata are well estabhshed. The Lias insects come from several 



