RECENT RESEARCHES IN THE DIATOMACER. 361 
Amphora.—In this genus the single endochrome-plate is only slightly 
scalloped. It separates at its middle portion by an incision springing 
from the ends throughout. ‘This in Amphora ovalis, Ehren., is very wide ; 
on the contrary in 4. Selina, W. Sm., it is very narrow. "The valves are 
altogether brown. On the broad more strongly arched girdle-band, each 
oil-globules are found in the central portion of the frustule. A cell- 
kernel is also distinct, which separates into two considerably before the 
process of cell-division commences. 
The newly-formed valves in Amphora are at first flat. In consequence 
of the peculiar structure of the Amphora, the line along which the two 
corresponding points of the valves move away from one another, in the 
In the middle plasm-mass no cell-kernel was notieed in any of the 
forms examined — Zpithemia gibba, (Ehren.) Kütz., E. ventricosa, Kütz., 
? 
thinks, are analogous to the plasm-bands of Anomoeoneis, ymbella, etc., 
: s us, canaliculi or tubes as Smith supposed, but, as Pritchard cor- 
Tectly observed, solid strips projecting inwards 
, The mode of development of the auxospores supplies a ete pine 
for uniting Zpifhemia and Amphora in a group distinct d eye 
Cymbelleg and Eunotia. According to the observations of a vA st 
Amphora ovalis, of Thwaites in Epithemia turgida and Æ. ym dn 
icosa, E. gibba, E. Sorex, and E. Zebra, of s 2i 
E. turgida and E. Zebra, of Itzigsohn in E. Goeppertiana, ys ” ds x 
as those of the author in Z. gibba, from two mother-celis ay 
