116 



imbedded. The surface is frosted or minutely punctured. 

 The apertures are oval, and armed with three triangular 

 denticles, which slightly lean over the opening; at the distal 

 margin there are three or four long slender bristles, which 

 readily break off. In the newer portions these hristles are 

 nearly always to be found, and the mouth is terminal and 

 almost hid from view by the teeth and prominent character 

 of the surrounding parts. 



This most nearly approaches the L. coccinea in character, 

 but differs so much as to show a specific difference. 



L. VARIOLOSA. Encrusting, calcareous ; cells oval, 

 alternate, or semi-alternate, punctured or frosted ; sepa- 

 rated from each other by a raised line. PI. xxii., 6. 



Lepralia variolosa, Johnston's Brit. Zoopb., p. 278, pi. 34, 

 fig. 4. 



Hab. On shells and stones, not uncommon. Polperro, 

 Goran, Mr. Peach. 



Encrusting; the crust is very closely adherent, circum- 

 scribed, and calcareous. It is of a yellowish flesh colour 

 while living, which in death changes to a sallow white, or 

 yellowish brown, but is very frequently of a pure white. 

 The cells are oval, somewhat imbedded, long and slightly 

 inflated ; their surfaces are minutely punctured or frosted. 

 They are separated from each other by a raised intercellular 

 ridge, which is marked by large depressions. The apertures 

 are round, but are liable to a little irregularity on the 

 proximal lip ; and on the distal margin are two long slender 

 diverging spines, which in dried specimens, are most com- 

 monly destroyed. 



L. VINCA. Calcareous, encrusting; cells ovoid, apertures 

 round, armed, with three or more spines ; the fissures 

 between the cells marked with two rows of punctures, with 

 bands of smaller ones embracing the ceils. PI. xxii., 

 fig. 7. 



Hab. On stories at low water mark ; common. Mera- 

 gissey bay. Polperro. 



This species very nearly resembles the Lepralia variolosa, 

 in almost every particular. Mr, Peach first pointed out to 

 me, what he thought to be specific differences, and after 

 examining a great variety of specimens, I am inclined to 

 adopt his view. The chief differences between the two, are, 

 that this is somewhat smaller, and whiter; the punctures 

 between the cells larger and more raised ; and the cells 

 appear as if bound down with chains from being surrounded 

 by bands of minute cells. 



