ItfSECTA. 51 



island, where four species have been found. The Clytia 

 Leachii of the chalk period has been beautifully restored 

 by Keuss.* Pairs of chelate claws occur in the upper chalk 

 which are referred to a hermit-crab (Mesostylus Faujasii). 

 Small Crustaceans, resembling in form the living Corystes, 

 abound in the gault (fig. 10, 2), but they are known to be 

 anomourous by the small size and dorsal position of the 

 posterior legs, and by the little plates intercalated between 

 the last joints of the tail, as seen also in the Dromilites 

 (fig. 10, 1 ) from the London clay. 



Class IV.— INSECTA, 



Char. — Body chitinous, articulated, with articulated and unci- 

 nated limbs ; head provided with jointed antennae ; 

 respiratory system tracheal. 



The fossil insects hitherto examined have afforded no new 

 types or forms of unusual interest. The oldest known, those 

 from the lower coal measures, resemble the Curculionidce and 

 Blattidm or Locusticlce of the present day. The lias limestones 

 have afforded a greater variety to the persevering skill of Mr. 

 Brodie : species of the genera Berosus, Elater, Gyrinus, Lacco- 

 phihiSy and Melolontha, and undetermined genera of the fami- 

 lies Carabidw, Bupreslidcc, Chyrsomelidm, and Telejihoridce ; 

 Panorpa-like insects of the genus Ortliophlebia ; dragon-flies, 

 Nepadce and Cimicidcc, Cicada, and the dipterous genus A silus. 

 Next in age is the insect depositary of the Stonesfield slate, 

 which affords the large wing-covers of Bujprestis BucMandi, 

 species of Prionus and Coccinella, and the great neuropteran 

 Hemerobioidcs. The Purbeck limestone has supplied, in addi- 

 tion, species of Cerylon and Colymbetes, Cyphon, Heloplwrus, 

 and Limnius; and examples of Stajohylinida 7 , Cantharidw, 

 Harpalidw, Hydropliilidm, and Tenebrionidw, Libelhda and 



* Transactions of the Academy of Vienna, vol. vi., 1853, 4to. 



