184 DEVONIAN FAUNA. 



Size. — Length 19 mm., width 14 mm. 



Localities. — Very abundant at Sloly Quarries. Specimens have been found 

 near Baggy Point by Mr. Townshend Hall. A single fine specimen from Saunton 

 is in Miss Partridge's Collection. 



Remarks. — The specimens from Sloly sometimes occur in beautiful states of 

 preservation, but are almost always more or less distorted. Occasionally they 

 appear almost circular in shape, and these my friend Mr. Townshend Hall was 

 inclined to separate under the manuscript name L. circularis ; but, having 

 examined his specimens, I believe that their shape is entirely due to pressure, and 

 that there is no reason to regard them even as a variety of the common form. 



On the other hand, I am more doubtful as to the identity of the fine dorsal 

 valve (PI. XXII, fig. 13) found by Miss Partridge in the Pilton Beds of Saunton. 

 Its almost oblong shape, almost horizontal posterior margin unbroken by the 

 apex, its very convex shoulders, its thin shell, and the five or six radiating lines 

 on the cast in front, seem to indicate that it is at least a marked variation from 

 the form of the species occurring at Sloly. 



2. Class— BRYOZOA, Elirenberg, 1832. 



1. Order— GYMNOL^EMATA, Alhnan, 1856. 



1. Sub-order— CRYPTOSTOMATA, Vine, 1883. 



Fenestellids are very abundant in the Pilton Beds ; but, as usual, their state of 

 preservation is such as not to lend itself to their easy determination. They can 

 in general only be obtained in fragments, crushed and drawn out in different 

 directions, so as to mask their relative dimensions. From the pressure which the 

 fronds have undergone it can rarely be said whether they were originally fan- 

 shaped or conical. From the nature of the rock it is impossible to obtain 

 sections. They occur for the most part either (1) in the condition of internal casts 

 when the cells are visible, but too frequently the dissepiments have disappeared, or 

 (2) in that of external moulds, in which case sometimes the cell-mouths may be 

 recognised, but the dissepiments are frequently blurred by the matrix or missing. 



Hence specific determination can only be very tentative. There appears to 

 be sufficiently clear evidence of the existence of at least three or four species, 

 but to define them so as to show their differences or their identity with fossils 

 occurring in other localities is almost impossible ; and it is not unlikely that if 

 better specimens were obtainable, differences would be found to exist between 

 some specimens which, under present circumstances, it is necessary to place 

 together. 



