320 POLYZOA INFUNDIBULATA. 



PLATE LV. FIG. 12. 



Lepralia innominate, Couch Corn. Faun. iii. 114. pi. 22. fig. 4. (very bad.) Lep. pec- 

 tinate, Peach MS. 



Hob. On stones and shells from deep water. Coast of Cornwall, 

 C. W. Peach. On bivalves dredged off Sana Island by G. C. 

 Hyndman. 



Polypidom forming a white, closely adherent, leprous crust on the 

 surface of the stone : cells calcareous, approximate, distinct, sub- 

 alternate, horizontal, shortly ovate, or sometimes almost orbicular, 

 and very like the shell of a Pecten in miniature, grooved with ribs 

 which radiate from the centre of the back to the edge ; aperture 

 small, round, armed with several short obtuse teeth or spines. 



The ribs or furrows of the cells appear to diverge sometimes from 

 a central umbo, and sometimes from the medial line, and in the former 

 case their likeness to the shell of the Pecten is very striking. These 

 cells resemble also the ovarian capsules of some species of Lepralia. 

 The spines of the aperture are frequently destroyed. 



28. L. SEMILUNARIS, " crust when dry opaJce white ; form of 

 cells not very distinct ; walls usually perforated ; apertures 

 semilunar, mostly furnished with an operculum ; a single- 

 pointed tooth arises from the anterior wall of each cell about 

 its centre.' 1 ' 1 A. H. Hassall. 



PLATE LVI. Fig. 4. 



Lepralia semilunaris, Hassall in Ann. and Mag. Nat Hist. ix. 411. Lep. pustu- 

 late ? Couch. Corn. Faun. iii. 113, pi. 22, fig. 2. 



" Two or three specimens of the above well-marked species have 

 occurred to me on old valves of Pecten maximus, trawled up off 

 Bray, near Dublin ; it is therefore most probably a deep-water 

 species. Its distribution is not confined to Ireland, as I have since 

 met with a single specimen on oyster shells from Burnharn, Norfolk. 

 In some cells the anterior tooth is broken off, leaving an aperture in 

 its place ; there is also sometimes an appearance of two spines, one 

 on either side the aperture, produced by the incomplete removal of 

 the operculum." A. H. Hassall. 



% % * * * Wall of the cel] roilg hened. 



29. LEPKALIA UNICORNIS, cells ovate, scaly, with a short 

 obtuse process or knob above the aperture, which is re 



with a distinct sinus in the upper margin. 



