66 



rays. Inter-stria? regularly punctate. This diatom differs from 

 I crebrecostatus by its more numerous striae and punctate ii 



strix. K eding ioo in number. 



This species is from the Straits of Macassar, in Mr. drove's 

 collection, in a slide No. 604, along with C. bian%ulatus % C. 



:, and var. Pfitzeri, C. intermedins, C. undulatus t etc. 



Campylodiscus trapezoidalis. Deby. (PI. XIV., f. 72.) 



Group of the Raphidae. 



Diam. of valves, o-no m.m. 



Area : length, o'oSo ; breadth, 0-083 m.m. 



Length of rays, 0*013 > length of striae, 0*040 m.m. 



Striae, 6 to 001 m.m. 



Puncta on striae, 6 to o"oi m.m. 



Valves with a trapezoidal inscribed line, with rounded sides 

 and sharp obtuse angles at the four corners. These angles ter- 

 minate about half way up the rays. Raphe reduced to a simple 

 line. Rays about 80 in number. Two strias to each inter-radial, 

 distinctly punctate. 



From Sta. Monica, Cal., from Mr. Rae's collection. 



Campylodiscus de Tonianus. Deby. (PI. XV., f. 75.) 



Group of the Hyalinae. 



Diam. of valves, 0*169 m - m - 



Area : long axis, 0T.19 m.m. ; short axis, the same. 



Area quite circular. Rays short, tapering ; 0*030 long , far 

 apart (width of inter-radials, o'oo6 m.m.) ; number of rays, 38. 

 Rays containing a row of from 16 to 20 minute double beads or 

 dots. Three marginal beads to each pair of rays. 



This species has been found in coral washings from Mauritius 

 (Doeg), and from Tamatave (Grove coll slide No. 582). 



Campylodiscus dentatus. 

 Group of the Hyalinae. 

 Diam. of valves, 0-183. 

 Diam. of area, 0099. 



Deby. (PI. XIV., f. 74.) 



