1863.] 



DAT LIAS OF DORSETSHIRE. 



291 



Trochus imbricatus, Sow. 



Gaudryanus, D' Orb. 



Turbo. 



Chemnitzia Periniana, D' Orb. 



Ammonites Bronnii, Rom. 



furticarinatus, Quenst. 



Nodotianus, D' Orb. 



Grenouillouxi, B 1 Orb. 



Henleyi, Sow. 



Bechei, Sow. 



laticostatus, Sow. 



Loscombii, Sow. 



fimbriatus, Sow. 



And several undetermined species. 



Nautilus inornatus, D' Orb. 



semistriatus, D' Orb. 



Belemnites clavatus, Blainv. 



longissimus, Miller. 



elongatus. Miller. 



acuarius, Sckloth. 



brevirostris, D" Orb. 



Bhyncholites. 



Xiphoteuthis Bechei, Huxley, MS. 



Geoteuthis, sp. 



iEchmodus. 



Ichthyosaurus communis, Conyb. 



tenuirostris, Conyb. 



2. The Green Ammonite-beds. — These beds, and the higher por- 

 tion of the non-micaceous marls, contain an assemblage of fossils 

 having many species in common with the beds below. Peculiar to 

 them amongst the Cephalopoda are Ammonites laticostatus, Sow., and 

 its aged and extraordinary variety A. heterogeneus, Y. & B. {A. hy- 

 bridus, D'Orb.), a species locally known as A. brevispina (but not of 

 Sowerby, nor yet I think a mere variety of A. laticostatus), and A. 

 Davoei, Sow., which is one of the most scarce Ammonites of our 

 locality. 



Inoceramus, n. sp. 

 Chemnitzia Carrucensis, D' Orb. 

 Pterocera liasina, U Orb. 

 Acteonina, sp. 

 Straparollus, sp. 

 Ammonites Bechei, Sow. 



Loscombii, Sow. 



laticostatus, Sow. 



heterogeneus, Y. Sf B. 



Ammonites Davoei, Sow. 



» sp. 



Nautilus semistriatus, D' Orb. 

 Belemnites compressus, Voltz. 



longissimus, Mill. 



Aptychi of Ammonites. 



Ichthyosaurus. 



Plesiosaurus. 



3. The Three Tiers. — These beds are very unfossiliferous, espe- 

 cially in the Golden Cap. The bones of Saurians are, however, occa- 

 sionally met with, as also Belemnites and the casts of phragma- 

 cones, and occasionally an impression or fragment of Ammonites 

 margaritatus, A. Loscombii, or of A. fimbriatus occurs in some of 

 the blocks. 



In the marls over them traces of but few fossils are seen, until 

 we come to the layer of small nodules, which contain Ammonites of 

 several species, and other shells. The shelly mudstone above con- 

 tains, as far as I can judge, the same forms as occur again in the 

 Shell-bed. 



4. The Shell-bed. — This bed underlies the Starfish-stone, and in it 

 I have found a rich collection of Mollusca, chiefly Conchifera. The 

 only two species of Ammonites which I have obtained from it are 

 A. margaritatus and A. Thouarsensis, D'Orb. One or two species 

 of Belemnites complete the list of Cephalopoda. Some small species 

 of Pleurotomaria, Trochus, and Chemnitzia occur not unfrequently ; 

 but the most abundant shells are those peculiar to this zone, which 

 extends from the small nodules to the Starfish-stone. Numerous 

 genera are represented, as the accompanying list shows. Fragments 



