50 SURFACE DIATOMACEZ FROM HONG-KONG HARBOUR. 
nation. The wedge shape of the frustule in section is 
caused by the connecting hoop between the valves being 
broadest on the dorsum or convex side. 
I am inclined to remove this diatom from the family 
Anguliferex and place it in that of the Coscinodixex. 
DESCRIPTION OF PLATE illustrating Dr Scorr LAvDER’s 
Paper on some Surface Diatoms from Hong-Kong 
Harbour. 
FIG. 
1. Chetoceros affine, parent frustule. 
2. + , filament increasing by self-division. 
3: " » side view of valve. 
4. ti » formation of sporangial endocysts. 
5. Endocyst of C. Lauderi. 
5a. 5 2 a variety. 
6. C.cellulosum, C. lorenzianuwm, with endocyst, usually 
considered an independent diatom under the name 
Dicladia capreolus, ete. 
6a. Awn of C. cellulosum, highly magnified. 
7. Endocyst of Chetoceros, front and side view. 
8. . ‘. ciliatum. 
9. C. compressum, with endocysts. 
10. Bacteriastrum varians. 
fol? ® » side view of intermediate frustule. 
12. JB. varians, sporangial endocyst. 
13. Palmeria Hardmaniana, side view of valve. 
14. 4 a perfect plant. 
