JOURNAL OF MICROSCOPICAL SCIENCE. 

DESCRIPTION OF PLATE X, 
Illustrating Dr. Greville’s paper on Plagiogramma, a new 
genus of Diatomacez. 
Fie. 
Te Dis ageationd Gregorianum ; side view. 
2.—The same; front view. 
3.—P. Jumaicense ; front view. 
4.—P. pulchellum ; side view. 
5.—The same; front view; chain of five frustules. 
6.—The same; a large example ; front view. 
7.—BP. tessellatum ; side view. 
8.—P. validum ; side view. 
9.—P. ornatum ; front view. 
10.—P. inequale ; front view. 
11.—P. pygmeum ; side view. 
12.—P. obesum ; side view. 
13.—The same; front view. 
14.—P. lyratum ; side view. 
15.—P. Californicum ; side view. 
16.—The same ; front view. 
17.—The same; front view, with fewer vitta. 
All the figures are x 400 diameters. 
