The Rev. P. B. Brodie on Insects in the Lias. 529 



In the absence of direct evidence on the subject, Mr. Sharpe en- 

 deavours to prove that Arenig and Arran Mowddy are at least as 

 modern as the Ludlow rocks, by showing that the upheaving of 

 these chains has broken up the parallelism of the cleavage planes 

 of the slaty rocks resting on them : assuming that these planes had 

 originally a constant direction in each district, their dislocation at 

 any spot would show that it had been disturbed subsequently to the 

 cessation of the cleavage process, and we may thus class igneous 

 eruptions as prior to, or posterior to, the cleavage ; and may then 

 connect them with the deposition of the formations, by observing 

 at what epoch the cleavage ceased in the district. In North Wales 

 and in Westmoreland, the cleavage only reaches into the Lower 

 Ludlow formation ; in Devonshire and Cornwall it continued later : 

 therefore Arenig and Arran Mowddy must have been upheaved after 

 the epoch of the Lower Ludlow shale. 



The memoir concludes with a general list of the species of fossils 

 found near Bala. 



" Notice on the discovery of the Remains of Insects in the Lias of 

 Gloucestershire, with some remarks on the Lower Members of this 

 Formation." By the Rev. P. B. Brodie, F.G.S. 



The lower beds of the lias, in which these organic remains occur, 

 are extensively developed in the neighbourhood of Gloucester and 

 Cheltenham, and occupy the greater part of the vale. In the upper 

 part of the lower beds, in a hard blue limestone, was found the ely- 

 tron of a coleopterous insect of the family Buprestidce, apparently a 

 species of Ancylocheira of Escholtz. This was the only fossil of the 

 kind met with by Mr. Brodie in this portion of the lias. With this 

 exception, the numerous fossil insects he has obtained occur in the 

 bottom parts of the lower beds near the base of the lias, which are 

 seen at several points in the neighbourhood of Gloucester. At 

 Wainlode Cliff, the lower beds of lias, resting on red marl, form a 

 bold escarpment on the south bank of the Severn, and afford the 

 following section in descending order : — 



1. Clay; 3 ft. 



2. Blue limestone, with Ostrea, &c. (the "bottom bed"): 4 in. 



3. Yellow shale with fucoid plants: 6 in. 



4. Gray and blue limestone, termed by Mr. Brodie "insect lime- 

 stone " from its characteristic fossils, passing into yellow shale 

 above, where it is nearly white, and has the aspect of a fresh- 

 water limestone : 3 to 5 in. 



5. Marly clay : 5 ft. 3 in. 



6. Hard yellow limestone, with small shells like Cyclas, plants and 

 Cypris : 6 to 8 in. 



7. Marly clay: 9 ft. 6 in. 



8. Bed with fucoid bodies : 1 in. 



9. Shale: 1ft. 6 in. 

 10. Pectenbed: 4 in. 



Nine feet below this is the bone-bed, 20 feet above which is the yel- 

 low Cypris limestone, and 26 feet 2 inches the insect limestone. The 

 total height of the cliff is about 100 feet. 

 Phil. Mag. S. 3. No. 155. Suppl. Vol. 23. 2 M 



