1886.] MICROSCOPICAL JOURNAL. 167 



hh. Cytioderni rough with pearly granules ; rays 4-7^ short, obtuse, 



margaritaceiim , 13^. 

 hh. " granulate ; end view 4-6 angled, sides straight, 



Aleriani, 132. 

 hh. " " end view 4- angled, angles with 2 spines, 



Novce CcBsareiE^ 14^. 

 hh. '' " end view 4-5 angled, sides concave, angles with- 

 out spines dilatatzim., 128. 



//. Angles in front view notched or otherwise divided {j'j)- 

 ii. Angles entii'e {kk^. 

 j'j. Surface granules emarginate or divided ; semi-cells broadly elliptic, 



asperum., 127. 

 jj. " not emarginate ; semi-cells elliptic . t}-7incata. 128. 



jj. '•'• not emarginate; semi-cells subsemiorbicular, angles 



truncate imiricattim., 12^. 



jj. Surface scabrous, semi-cells elliptic scabnim^ 130. 



jj. Surface tuberculate ; sides at base convex, spinous ; a central, spherical, 



spinous projection conspicuous bullosum.* 



jj. Surface tuberculate ; sides at base concave ; no central protuberance. 



ttiberciilatum . * 

 hh. End view sides concave (//). 



hh. " sides nearly sti'aight, very slightly convex {iiii). 



hh. *•' sides convex ; semi-cells subsemiorbicular, wz^^r/ra/?/?//, i3y. 



//. Semi-cells twisted ; 2-3 times longer than wide, elliptic or oblong, 



alternaiis., 128. 

 //. Semi-cells not twisted {mjti) . 

 mjn. Front view ends concave ; end view angles rounded . striolati/m, 126, 

 i?zm. '' " end view angles acute . . Pringlel.^ 133. 



mm. Front view ends convex ; end view angles crenate, sides smooth, 



crenatum., 126. 

 mm. " " end view angles not crenate, somewhat trun- 

 cate dilatatum^ 128. 



mt. Diameter yyVir "^- i^S'') <^i' ^^^^ pygmceum., 128. 



mt. '■ greater than ^7,^0" i"- {'^S'A i ^"^^ broadly truncate, sides 



slightly convex or nearly straight, converging . botrophilum. 131. 

 nn. Diameter greater than ^^fVo" ^^^- (^S''-*) ! ^"^ rounded, sides convex ; 

 semi-cells elliptic .... rugulosum^ 127; punctidatiim.., 127. 

 00. End view 3-radiate or angular, sides nearly straight {pp). 

 00. " '' *•' sides concave (rr). 



00. End view 4-radiate or angular {xx) . 



pp. Cells spinulose on the whole surface aculeatum., 140. 



pp. " " on the margins only setigertim., 141. 



rr. Cells spinulose, a short, irregular process on each side, 



controversum , 1 43 . 

 rr. Cells spinulose on the margins of the long, colorless, diverging arms, 



aspinosum., 143. 

 ss. End view triangular or 3-radiate {tt) . 

 ss. " 4 or 5-angular or radiate {uu) . 



ss. End view circular, with usually 9 short, marginal, notched processes, 



Eloiseanum.^ 149. 



tt. End view margins smooth ; spines short ; semi-cells in front view twice 



as wide as long avicula, 133. 



*Journ. R. Micr. Soc, Feb., 1886. 



