I860.] -WEIGHT LIAS. 4<>5 



these beds was obtained. The rocks consist of dark-grey or bluish 

 shales and clays, with irregular and inconstant beds of dark-grey 

 argillaceous limestone, the shales being in parte nodular or lami- 

 nated, the clays thick and tenacious ; the nodular portions of the 

 shales were very fossiliferous. This zone forms part of the Cardinia- 

 bed of the local geologists in Warwickshire, where it appears to be 

 exposed in several localities. I saw in Mr. Tomes's collection some 

 very fine specimens of Ammonites obtusus, Am. multicostatus, Am. 

 Broolcii, and Am. Sauzcanus, d'Orb., collected by him from the Am. 

 obtusus beds ; and in Mr. Kershaw's collection I saw a series of Am. 

 Sauzeanus, d'Orb., from DarHngstoke near Shipton-on-Stour. 



Dorsetshire. — At Lyme Regis the zone of Ammonites obtusus attains 

 a considerable thickness, and is well exposed in the coast-section. 

 The beds rise on the shore about half a mile east of Charm outh, and 

 consist of thick beds of dark marls, which rest upon the Table-bed, 

 formed by liroad Ledge. The lower part of these marls contain 

 numerous compressed Ammonites and layers of nodules forming 

 cement- stones. Above these succeed shales and clays, thin bands of 

 limestone, and thick beds of shale and marls with mudstones. Above 

 these are inconstant bands of limestone containing septaria, in which 

 gigantic examples of Am. obtusus, Am. stellaris, and Am. Broolcii are 

 found. The following section shows the relative position of these 

 beds. 



Sect ion from Broad Ledye to Cornstone Ledye, near Charmouth. 



t. t Litiiology. o. Organic Remains. 



jNo. it. in. 



1. Dark-grey limestone. " Corn- 



stone Ledge." 



2. Dark-bluish maris 20 



3. Dark-greyish limestone 10 Ichthyosaurus platyodon and I. inter- 



medins. 



4. Dark clays. 



5. Dark limestone, with septaria. Nautilus striatus, Ammonites Brooiii, 



and Am. stellaris (very large). 

 0. Dark shale. 



7. Dark limestone. " Upper Ce- 



lllClll-lll ll." 



8. Dark shales, containing mull- Tnoceramus. Saurian remains, 



-!• me nodules. 



'.). Thin band of limestone. "The Extracrinus Sriareus, 



Pentacrinite-bed" 



in. Darl il | 



11. I tars limestone, ,-• , , ,, 

 ,.,,.,,, r "Kre-ledgft 



I •_'. Dark shale. ° 



18. Dark limestone. ) 



II. Dark shale. " Split-ledge." 



L5. Dark limestone Ammonites plantcosta. Bow., mul .-l«i. 



Stni/liii, S. i\\ . 



16. Dark shales Saurian skeletons, 



17. Greyish limestone A nonitet obtusus, Sow., and Am, 



BtrekH, Sow., crystallised forming 

 the " Tortoise-ammonites." 



IS. Dark marls, with nodular The nodules "I" these lowex ><inent- 



massea 2o o beda contain Saurian remains, 



19. Dark indurated Bhale and 



limestone. "Broad Led • I Overlies the Lima-beds east of Lyme, 



