LEPRALIA HIPPOPU8. 309 



LEPRALIA HIPPOPUS, Smitt. 

 Plate XXXIII. figs. 8, 9. 



LEPRALIA HIPPOPUS, Smitt, CEfv. af Kongl. Vet.-Ak. Forh. 1867, Bihang, 

 Krit. Fort. iv. 20 and 127, pi. xxvi. figs. 99-105. 



Zooecia ovate, moderately convex, not deeply divided, 

 arranged quincuncially, occasionally bordered by a 

 raised line ; surface almost smooth, with a hyaline 

 lustre (in the young state), or obscurely granulated or 

 roughened by anastomosing ridges, with a number of 

 large punctures round the edge, and usually a central 

 mucro ; orifice longer than broad, well rounded and 

 expanded above, constricted on each side a little above 

 the lower margin, which is slightly curved outwards ; 

 oral spines 2-4 ; an avicularium, with a rounded man- 

 dible pointing upwards, on one side, often a little below 

 the mouth, placed obliqely. Ooecia globose, subim- 

 mersed, smooth or pitted, with a prominent mucro on 

 the front. 



RANGE OF VARIATION. In young marginal cells the form 

 is distinctly marked, the front moderately convex, rising 

 towards the central umbo ; the surface almost smooth, or 

 slightly roughened, or reticulated, glossy, and of a bluish 

 grey tint. In the central portions of the colony the walls 

 are much thickened and roughened, and, as a conse- 

 quence, the divisions between the cells are almost obli- 

 terated, the surface is of a more uniform level, and the 

 mouth more or less depressed. The avicularia vary in 

 position : sometimes they are placed about the middle of 

 the side of the orifice, sometimes a little below it ; and 

 occasionally there are two, one on each side. Rarely an 

 elevated avicularium of an abnormally large size is met 



