204 MESSES, p. r. KENDALL AND E. G. BELL ON 



to the oxidation of the upper part, though it should he noticed in 

 this connexion that the yellow clay is almost destitute of fossils, 

 only fragments being found. The washings yield, according to 

 Mr. Wood, about 1 per cent, of angular rock-fragments, mostly killas, 

 and some vein-quartz ; the finer washings also show abundance of 

 fine angular quartz grains, and some mica. 



The clay-bed, No. 4, seems to be the deposit in which nearly all 

 the shells and other remains are found ; but this does not seem to 

 be uniformly fossiliferous, as a large quantity obtained for exami- 

 nation by Mr. Wood was very barren, while careful washing and 

 sifting of about thirty pounds weight from another part yielded 

 nearly the whole of the smaller species of MoUusca recorded, and 

 brought to light many species of Rissoa, Odostomia, and other 

 genera, with a quantity of the fry of the larger species. 



The fossils are in general very strong and in good condition, the 

 finer strige and ornamentation even of the Foraminifera being well 

 preserved, probably owing to the tenacious character of the matrix. 

 It is remarkable, however, that the larger bivalves are almost all 

 fragmentary, the oysters alone being generally found in a tolerably 

 perfect condition : this may probably have been owing to the pre- 

 sence in the St. Erth sea of a large number of predatory fishes, 

 such as the Wolf-fish (Anarrhichas lupus), which breaks up the 

 strong shells of Nucula and Pectunculus with its solid pavement of 

 teeth. 



So far as investigation has been carried out in this deposit, nearly 

 all the palseontological evidence obtained has been confined to the 

 Invertebrata ; the only remains of a higher class consist of a few 

 undeterminable fish-vertebrae and otoliths. 



Several species of Polyzoa occur, all of which have a wide geo- 

 graphical range, mainly southern; the encrusting forms were at- 

 tached to the interior of Gastropods, and single detached cells are 

 found in the fine washings ; but it is a remarkable fact that we have 

 not found a single example upon an oyster, Pecten, or any other 

 bivalve which usually forms their habitat. The following species 

 have been determined : — 



Melicerita Oharlesworthii, M.-Edw. I Lepralia Pallasiana, Moll. 

 Salicornaria (Oellaria) sinuosa, Hassall. \ (Microporella) violacea, Jb^ws^ow. 



All these occur in the Coralline Crag and the Italian Pliocenes. No 

 characteristic northern species has been found. Fragments of Bala- 

 nus occur, and several species of swimming Crabs are represented 

 by chelae and fragments of the carapace. Detached plates of Echini 

 and portions of the test of an irregular Echinid abound ; also the 

 spines of both groups. We have also found three or four species of 

 Annelida and a Nullipore {Melobesia, sp.), and in the fine siftings 

 spicules of calcareous sponges, upon which Dr. Hinde has appended 

 a note. Shells bored by Oliona are also found. 



An interesting discovery is that of an Alcyonarian. 



Plates referable to the Holothurias (Cucwmaria, sp.) are fairly 

 ommon. 



But perhaps the most remarkable of the fossils of this deposit 



