380 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 10, 



description by Sir Philip Egertou, and is figured in Plate XIV. 

 fig. 13. This represents the mesosteruum, metasternum, and ven- 

 tral surface of the abdomen of an insect, which, from its structure, 

 must have been of hea^y aspect and most probably of slow motion, 

 and which must have lived in dark and obscure situations. 



This I infer from the circumstance that the elytra are deflexed at 

 the sides, forming a groove for the lateral margins of the abdomen, 

 a peculiarity which implies — 1 st, that the elytra, if separate, coidd 

 only be raised with difticulty ; 2ndly, that they were more probably 

 soldered together along their dorsal suture ; and, 3rdly, that the 

 wings were wanting. These are characteristics of several groups of 

 beetles, amongst which are the Darkling Beetles {BIaj};iidce) and the 

 larger species of the Ground Beetles {Carabidce). In these families 

 short broad forms occiu* in the genera Blaps and Pimelia, and ui 

 Cychrus. 



As to the decided affinities and position of this fossil beetle, we 

 must take into consideration the form of the two sterna and the 

 form and number of the segments of the abdomen. The recent 

 investigations of Coleopterists have proved that these characters, 

 and especially the latter, are among the best and safest clues to the 

 natural classitication of the Order. In the fossil before us, the meso- 

 sternum is advanced in a triangle between the cavities for the inser- 

 tion of the middle legs ; the metastenaum is very short, and is ex- 

 tended slightly backwards, and divided mto two small lobes by an 

 impressed hue ; and its hiuder notched edge meets the advanced 

 wide lobe of the short basal segment of the abdomen. The second, 

 third, and fomth segments of the abdomen are of nearly equal 

 width ; but the extremity of the fourth and the remainder of the 

 veutral surface are abraded. Now the relative size of the sterna 

 agrees better with the Blapsiche than with the Carahidie ; but the 

 short basal segment of the abdomen occurs in Cychrus, only it is 

 soldered to the next segment, so as to be but little distinct. 



From the appearance of the fossil, I shoidd conceive that the lost 

 extremity of the abdomen comprised only a single segment ; if so, it 

 woidd be eveu longer than the precethug, whereas in the Blapsidte, 

 owing to the large size of the basal segment, the two terminal seg- 

 ments are very short. The fossil beetle diflers, therefore, from both 

 these tribes, and it is much to be regretted that its fragmentary con- 

 dition will not allow of its relations being more satisfactorily deter- 

 mined. 



A small spiral univjxlve shell is imbedded in the same slab with 

 the beetle. 



II. Large fossil Dragon-fly from the Stonesfield 

 SL.4.TE. PI. XYII. fig. 20. 



A pair of large wings of a Dragon-fly found in the Stonesfield Slate*, 

 at Eyeford, on theCotswolds, bythe Rev. P. B. Brodie, are represented 



* For an account of the Stonesfield Slate of Gloucestershire, see a paper hy 

 Messrs. Brodie and Buckiuan, Proc. Geol. Soc. vol. iv. p. 437, 1S44; see also 

 Broiiie's ' Fossil Insects," p. 3?. &c. 



