PROCEEDINGS OF THE SOCIETY. 
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9. Biddulphia echinata. — From Vuna Point, Island of Taviuna, Fiji 
Islands. This diatom was described by Mr. Kitton in the Journal of 
this Society for June 1888; ho therein remarks that “this species 
seems to be very subject to abnormal development.” The slide exhibited 
shows this very clearly. It will be noticed that the surface is covered 
with triangular scales or spines. 
10. Ceratulus Smithii , frustulesand valves. — From Sheerness-on-Sea. 
Examining the centre frustule it will be noted that none of the horns or 
spines of either valve are opposite to those of the opposite valve ; the 
hoop extends partially over the upper valve, as may be distinctly seen 
on the edges of the frustule. The valves surrounding the frustule are 
in pairs, being really two frustules divided into halves by means of a 
mounted bristle. The upper and lower valves are viewed from the 
inner side, while those to the right and left are seen from the outside. 
11. Climacosphoenia moniligera. — From gathering in Japan. This 
is not a rare form in warm seas, but the slide exhibited was mounted to 
show the formation of this diatom in its entirety. The diatoms placed 
third from the ends are front views of complete frustules ready for self- 
division, the others arc valves, or parts of valves, viewed either from 
within or without. 
12. Coscinodiscus clegans var. spinifera. — From deposit at Oamaru. 
This slide exhibits both aspects of the valve. The centre valve, on 
edge, shows the short spines on the circumference as well as the depth 
of the depression in the centre of the valve. 
13. Cymatopleura ellipticci. — From Wey bridge. This is only a 
very common fresh- water form, but is exhibited as being the first slide I 
mounted with a view of showing both aspects of the valve or frustule. 
I scarcely know how I did it, as I only had an ordinary 1-in. simple 
lens. I now use for this work a Stephenson’s binocular with a power of 
40 or 50 diameters. A face view of the valve does not give so good an 
idea of the depth of the furrows as does a front view of the frustule. 
14. Dicladia capreolus. — From “ Cementstein,” Sendai, North Japan. 
This form, which was described as a distinct species by Ehrenberg, is 
now regarded as being a “ spore ” of Chsetoceros dicladia , and is figured 
in situ in Castracane’s * Challenger ’ diatoms. 
15. Eupodiscus Argus. — From Tampa Bay, Florida. These diatoms 
from Tampa Bay appear to have the outer structure less silicified than 
is usually the case with this form. In all of the outer valves now shown 
the outside structure is comparatively thin, but the centre valve is a 
gem, the outside structure being entirely absent with the processes quite 
perfect. This valve resembles an Aulacodiscus , to which genus Eupo- 
discus Argus undoubtedly belongs. 
16. Hemiaulus Kittoni. — From “ Cementstein,” Mors Island, Jut- 
land. The centre diatom shows the position of a “ spore ” within the 
body of the frustule ; the “ spores ” are also shown entirely isolated. 
I am unable to give any further information about these “ spores ” than 
that the very similar forms Dicladia capreolus and Hercotheca mammi - 
laris , described by Ehrenberg as distinct genera, are now known to be 
the somewhat similar spores of Chsetoceros. 
17. Hercotheca mammilaris, fossil. — From Howard’s Grove, near 
Richmond, Ya. These are “spores” of a species of Chsetoceros , though 
