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gathered from the spoil bank ; whilst B. a'picmrvatus and B. 

 subaduncatus are scarce. B. compressus is also one of the rarer 

 forms. From the large number of specimens of the class 

 available, one would have thought that adherent shells might 

 be expected. Some hundreds of them were collected and 

 washed, in the hope of obtaining booty ; but all they yielded 

 proved to be merely numbers of young Plicatula spinosa, and 

 traces oi Annelids, Serpulce, &c. No Crania, Discina, or Thecidea : 

 the conditions account for their absence — agitated quicksands 

 prevented these portions of drifted Belemnites from becoming 

 the nidus of the more delicate adherent genera of brachiopoda. 

 (b) Gasteropoda. — From the observations made before on the 

 particular Laminarian depth of the beds of the Spinatus Zone, 

 we may easily infer the nature of its univalve inhabitants, such 

 as usually people this sub-littoral part of a shore, and subsist 

 on its vegetation. Upon the broad surfaces of the strong coarse, 

 Algoe growing here, the herbivorous kinds delighted to pasture. 

 I cannot recall to mind any bed of the Lias, at any rate of the 

 Middle Lias, where gasteropods occur in such numbers ; but 

 though they congregate thus, the species are few. The shell, 

 or rather cast, constantly met with and always accompanying the 

 flattened stems of plants, is a Turbo, one of the holostomatous 

 class of gasteropod that lived exclusively upon vegetation. 

 Our shell is the Turbo paludinceformis (Phasianella) of ScHiJBLEE, 

 with the test almost smooth ; it is about half-an-inch or 

 more in length, and, as we may suppose from the number of 

 synomyms with which it has been honoured, is a species of 

 rather vai'iant form. It is the Turbo cyclostoma of Golsfuss and 

 MuNSTEK, and is also figured under that name by Quenstedt ; 

 it is the T. cyclostomoides, and the T. littorinceformis of 

 DuNKER and Koch j the T. Kochii of H. Schlonbach, in his 

 Eisenstein der mitt. Lias, 1863, and of Emerson, in his Lias 

 von Markoldendorf, 1870 ; and further, the T. nudus, of 

 MiJNSTER, and other authors. Doubtless it is the same species 

 figured by Oppel, Mittlere Lias, 1853 ; and we surmise that the 

 shells passing under the name of T. Kochii, T. nudus, and T. 

 Itys, by TJ. Schlonbach and by Emerson, in their respective 



