SOME Niw AND RABE DIATOMS. 



of angles with very short radiating lines; surface strongly pnnctate." Distance between 

 angles, .0014 to .0018 iuch. Cambridge Estate, Barbadoes. Plate III, Fig. 9. 



TriceratitttH fractnm. N. 8p., 11'., and C. Large; angles broadly rounded 

 forming s-mieircles; sides deeply concave; margin marked by a row of prominent cel- 

 lules; a small, blank space at centre; surface of valve covered with radiating lines of 

 fine granules; central portion depressed below surface of the angles, and bordered by 

 an undulating, circular line, having the appearance of a fracture. On each angle there 

 is a semilunar, nodular elevation, very finely granulated. Distance between angles, 

 .0042 inch. Springfield Estate, Barbadoes. Plate III, Fig. 8. 



Aclinoptychus Wittily Janlsch, Schm. At. 100 f. 12; Jeremie Deposit, Hayti. 

 lor. s< tifi/oritiis .- not. var., W. and C. The areolation in the figure in the atla«, is 

 very coarse. In our variety, there is a round hyaline space at the centre; the angles are 

 alternately acute and broadly rounded; processes three, prominent, quite elevated above 



neral surface of the valve, situated on the acute angles, projecting to edge of 

 margin, extending inward half way to centre. Newcastle Estate, Barbadoes. Diame- 

 ter, .005 inch. Plate V, Figs. 1, 2. 



The artolation in this variety is very fine. 



Coscinoeliscus ohlongus, Oreo., Trans. M. S. 1866 p. 4 PL 1 f. 9, 10; Schm. 

 At 66 f. 10, 11. "Disc more or less oblong, having the centre depressed; an umbilicus 

 containing a number of subremote granules; surface filled up with radiating lines of 

 granules, diminishing in size next the umbilicus and toward the margin, where they re 

 Bemble minute puncta." Size variable, often .005 long by .0025 inch wide. Springfield 

 Estate, Barbadoes. Plate V, Fig. 4. 



Trieeratium radiatum, Bright. M. S. 1856 p. 275 PI. 17 f. 14; Trans. M. S. 

 186 I PI. 7 f. 4; Prit. Inf. p 854; Van Ileurck's Syn. PI. 112 f. 8: (Biddulphia t Grun.) 

 Valve with straight sides; angles very slightly produced; a small circular blank space 

 at centre, from which a dark line extends to the middle of the margin of each side; 15 

 to 20 heavy lines extending from each margin one-third the distance to centre; surface 

 of valve covered with radiant rows of very fine puncta. Distance between angles, .0024 

 inch. Springfield Est., Barbadoes. Plate IV, Fig. 6. 



Trieeratium crenatum, Kitton; Piit. Inf. p. 939; 

 I Di8Coplea midulata, E. M. PJ. 33-xviii f. 3);= 



