318 POLYZOA IKFUNDIBULATA. 



coarsely punctured like the end of a thimble : cells sub-contiguous 

 arranged in regular semi -alternating rows, slightly raised anteriorly, 

 the aperture roundish or semi-oval, entire, either sinuated or armed 

 with a small tooth on the upper edge : ovarian capsules globular, 

 smooth, and pearly. 



When dried the crust can in some instances be separated from its 

 foreign base in small pieces, but in general it is very firmly adherent, 

 and has a decided tendency to grow in a circular form. The patches 

 are often upwards of an inch in diameter. The central cells are so 

 deeply immersed in the crust that their form is rendered indistinct, 

 and even the intersticial punctures will disappear ; but the marginal 

 cells in general exhibit the character of the species sufficiently. In 

 a good specimen in my possession, many of the cells are character- 

 istic, but many others are punctured all over ; the interstitial spaces 

 between some are smooth, between others punctured, and between 

 others again they are raised into elevated lines or septa. I fear that 

 a tact, to be acquired only by some experience in their examination, 

 is often necessary for the discrimination of Lepraliae. 



" Lepralia variolosa is rather plentiful, and Proteus-like. I have 

 seen it with two spines on the distal edge of the aperture ; they run 

 side by side at first, and then turn upwards." C. W. Peach. 



25. L. FENESTRALIS, " encrusting, calcareous; cells urceolate, 

 slightly immersed, semi-erect, and reticulated ; aperture con- 

 tracted, circular, with a slight tooth on the proximal %>." R. 

 Q. Couch. 



Lepralia fenestralis, Couch Corn. Faun. iii. 117. pi. 22. fig. 8. 



Hob. " On stones at short distances from the shore, not uncom- 

 mon," R. Q. Couch. 



" This rarely exceeds three-fourths of an inch in diameter ; it is 

 calcareous and encrusting. The cells are urceolate, and closely ar- 

 ranged in circular rows ; they do not, like most other species, lie 

 horizontal to the crust, but the oral portions are elevated, or semi- 

 erect. The surface of the cells is rough ; several calcareous lines 

 run longitudinally their whole length, and these are crossed nearly 

 at right angles by shorter bands, which give the surface a net-work 

 appearance with square meshes. This window-like surface has the 

 interspaces filled with a transparent membrane, which is more appa- 

 rent in dried than in living specimens. The aperture is small, con- 

 tracted, and circular, with an irregularity on the proximal lip." R, 

 Q. Couch. 



