BRODIE -PURBECK INSECT BEDS. 479 



strata, occupy a rather central position in the lower Purbecks in 

 Durdlestone Bay, and are well described in the Section in Austen's 

 'Guide' above referred to. There are two or three white earthy 

 limestones, like chalk more or less indurated, in which relics of 

 Insects are most abundant. The middle one of these is the richest, 

 especially for groups of elytra and wings, but they are by no means 

 confined to this portion of the formation, having been noticed (as 

 before observed) in the " Pecten beds " above, and again lower 

 down at No. 128 in Mr. Austen's List, near the second chert beds, 

 where they are associated with Archcsoniscus. Few or no other 

 fossils, except small fragments of carbonized plants, occur in the 

 white Insect-beds at the top of the lower Purbecks. In these I have 

 only seen one small Fish, which was discovered by Mr. W. R. Brodie, 



ft. in. 



97. Soft shaly band 4 



98. Chertyband 4 



99. Marly limestone 1 3 



100. Rubbly limestone 1 



101. Marly limestone 8 



102. Rubbly blue marly limestone 3 



103. Rubbly white marly limestone 4 



104. Marly limestone, with vegetable remains, wings, elytra, and bodies 



of /wsee<s, abundant in patches 3 



105. Slaty marl 1 6 



106. White marly limestone, with a harder band in the centre, con- 



taining /wsec^ and vegetable remains 4 



107. Blue slaty marl 1 6 



108. Hard marly limestone 1 6 



109. Blue slaty marl 1 6 



110. Laminated sandy marl, with traces of Vegetables, Fish-scales, 



Serpula, small Cardium, and a cherty band with Melania. 



111. Marl, with Cyprides and shells {Ledd) 1 6 



112. Slaty marls 4 



113. Marly limestone, containing /jisec/s and a branching Plant 2 



114. Blue laminated shales and marl and gypsum 3 



[The beds here are hidden by the fallen cliff.] 



115. Slaty marl. 



116. Cream-coloured marl, full of shells (Car<fzMm), with vegetable and 



Insect remains 2 6 



117. Cherty band, full of shells, chiefly univalves, and Cyprides. A 



small Cardium abundant 4 



118. Slaty coloured marls 1 6 



119. In&nvaXtA m&x\%, elytra of Insects, Cyprides, 2iaA\in\\a\\es 3 



120. Bluish marl. 



121. Indurated marl, with many Bivalves. 



122. (Chff disturbed.) 



123. (Ditto, and contains blocks from several beds.) 



124. Cypris shales 3 



125. Indurated marl and shales alternated ; with vegetable remains and ] 



Archceoniscus S4 6 



126. Band of white marl, vertically cracked J 



1 27. Hard band, containing y^rc/i«?o?!2scM.9 5 



128. Blue and brown indurated marl, with a large species oi Archao- 



niscus, Cyprides, Estlieria, and shells. 



The whole of the above were deposited in brackish water ; and it is worthy of 

 remark, that here we have the greatest number and variety of Insect remains. 



