SOUK NEW AM) RAKE DIATOMS. 



divided by transverse lines into punctated compartments. Diameter between angles, 

 .0027 inch. Cambridge Estate, Barbadoes. Plate III, Fig. 1. 



Asterolampra marginata, (Br.) Grev. Trans. M. S. 1862 p. 50 pi. 8 1'. BO; 

 = Craspedodiscus Tnarginaius, Bright well, M. J. 38(30 p. 95 pi 5 f . 7; Prit. Inf. pp. 

 832, 839. "Two-thirds of the radius of the valve occupied with radiating lines of hue 

 puncta ; umbilical lines very short ; segments forming a narrow, punctate border ; nar 

 row portion of rays obsolete." Diameter of disc, .0045 inch. Number of rays from 14 

 to 22. Plate V, Fig. 7. 



Var, minor, W. and C. Much smaller, .0025 inch in diameter ; puncta oc- 

 cupying one-half the surface of the valve, and increasing in size toward the centre ; um- 

 bilical linesproportionately longer, and fewer in number. Both from Springfield Estate, 

 Barbadoes. Plate V, Fig. 8. 



Entogonia amuhilis, Grev., M. J. 1863 p. 10 pi. 10 f. 21 ; Schm. At. 88 f. 5. 

 "Valve with slightly convex sides, and obtuse angles ; border compartments punctated, 

 pseudo-nodule circular, very prominent ; central triangle with slender, radiating costa* ; 

 the angles penetrating a circular pseudo-nodular space." Distance between angles, 

 .004 in. Cambridge Estate, Barbadoes. Plate III, Fig. 5 ; Var., Fig. 4. 



The genus Entogonia was instituted by Dr. Greville in 1863, for the reception of 

 seyeral species of previously described Triceralia, and is distinguished by the following 

 generic characteristics ; "Frustules with the lateral view triangular, containing a central 

 triangular figure ; having a broad border divided by transverse costaB into punctate or 

 cellulate compartments." The Genus is divided into two sections ; those with a blank 

 central triangle, and those in which it is filled with various markings. He has de- 

 scribed 14 species, to which none have been added. They constitute a distinct and 

 prominent genus, notable for beauty and rarity. 



Triceratitim J'ettsettian/wm, Gum., Hedwigia, Vol. V. p. 145 ; Schm. At. 

 77 f. 15, 16. Large ; sides concave ; angles slightly produced, rounded ; noduh s smooth ; 

 valve coarsely and irregularly cellulose ; cellules extending over the margin, producing 

 a heavy, roughened appearance ; a small number of heavy dark lines extending from 

 margin a short distance inward upon the valvular surface. Distance between angles, 

 .0035 inch. Newcastle Estate, Barbadoes. Plate III, Fig. 15. 



Trie, replettim, Grev., Trans. M. S. 1866 p. 83 pi. 9 f. 18 ; var. Balearwa, 



