CELLErORID^ : LEPRALIA. 321 



Plate LVII. Fig. 1. 



Bereuicea cocciiiea, Johnston in Trans. Newc. Soc. ii. 267, pi. 12. fig. 5. — Lepralia 

 coccinea, Johtis. Brit. Zooph. 27<3, pi. 34. fig. 1-3. HassaU in Ann. and Mag. N. 

 Hist. vii. 367. Couch Corn. Faun. iii. 115. IF. Thompson in Ann. Nat. Hist. 

 V. 253. 



Ilab, On rocks near low-water mark, and on the roots of the 

 Laminaria cligitata. Common. 



Poljpidom forming a closely adherent, calcareous crust, often an 

 inch and upwards in diameter, tending to spread circularly, but fre- 

 quently diverted from this its normal form, roughish to the naked 

 eye, generally of a flesh-red or purplish colour, but sometimes pure 

 white, and this colour it almost always acquires after being dried for 

 some time. The cells are disposed in contiguous rows, separated by 

 a furrow ; they are either opposite or semialternate, ovate or urceo- 

 late, horizontal, the walls rough or scaly, rather thick and coarse, 

 opaque or silvered, the aperture constricted, entire, roundish, with a 

 sinus in the upper side, and over this there is an obtuse process ori- 

 ginating a little behind the margin. In many of the cells towards 

 the centre, there is on each side of the aperture, an obtuse obliquely 

 truncate hollow process with a terminal slit, which seems to be the 

 opening of an abortive or partially developed cell. The ovarian 

 vesicles are globular, white, deeply grooved, the grooves radiating 

 from the apex : they are produced often in great numbers, and are 

 situated immediately above the aperture, between its rim and the 

 mucro. 



There is a variety of a silvery-white colour, with cells of a more 

 globular shape, and thinner parietes. The character of the aperture 

 is hence more distinctly defined, and its margin more raised. 



SO. L. Ballii, cells shortly cylindrical, digliily raised, iliicTc 

 and granulous, the aperture circular with a mucro on the 

 'proximal margin, and a large open auricle on each side. 



Plate LVI. Fig. 5. 



Hah. On various bivalve shells dredged off Sana Island by G. C 

 Hyndman. Coast of Cornwall, C. W. Peach. 



A fine species, forming a rather thick white calcareous crust with 

 an undefined margin, consisting of a single layer of rowed cells very 

 obvious to the naked eye : cells contiguous, short, cylindrical, raised 

 towards the aperture, the walls thick, opaque, rough with small 



Y 



