with descriptions of new Genera and Species. 203 



slightly cavate posteriorly : anterior spines four, straight, wide 

 at the base and pointed; the occipital pair taller than the lateral. 

 Lorica yjyth inch. 



B. dorcas. Lorica ovate, or subconical ; occipital edge with 

 four long slender spines, the middle pair curving forwards, and 

 bent first from, and then towards, each other, like the horns of 

 an antelope ; mental edge undulated, with a notch in the centre. 

 Lorica ^th inch. 



B. amphiceros. 



B. urceolaris (?). 



B. rubens. 



B. Millleri. Kenilworth Castle. 



B. hepatotomus. Lorica ovate ; occipital edge cut into six saw- 

 like teeth much shallower than in B. Mulleri, with the central 

 notch deeper and rounder than the rest ; mental edge with four 

 rounded lobes separated by notches : posterior extremity with two 

 nipple-like points : biliary (or pancreatic) glands very large and 

 cleft into two 'lobes almost to their base. Hence the name, 

 r}7rap, the liver, and refjuvco, to cut. Lorica yj^rd inch. Sea- 

 water ; mouth of the Neeze, Essex. 



B. Bakeri. 



B. annularis. Lorica hexagonal-oval in a dorsal aspect ; occi- 

 pital edge with two small teeth divided by a rounded notch (in 

 some specimens there are obsolescent traces of a lateral pair) ; 

 mental edge slightly undulated, sometimes with two low points 

 divided by a notch, like the occiput, but still more faintly : pos- 

 terior extremity with two short, blunt, well-marked processes. 

 The general surface is roughened with angular ridges, and is 

 sometimes subopake and brown. Lorica g^th inch. This 

 curious species has relations with Noteus and with Pterodina. 



Pterodina patina. 



P. elliptica. 



P. clypeata. Sea-water ; mouth of the Neeze, Essex. 



Gen. Pompholyx. Two frontal eyes : foot wanting : rotatory 

 organ double in the rear, entire in front : eggs attached behind, 

 after deposition. The name alludes to the resemblance of the 

 lorica to a round flat smelling-bottle. 



P. complanata. Lorica much depressed, nearly circular, with 

 the lateral edges rounded; anteriorly truncate; occipital edge 

 gradually rising to a central blunt point ; mental edge with two 

 rounded lobes, divided by a central notch. Lorica 7 ^th inch. 



De Beauvoir Square, July 28th, 1851. 



