DUBLIN MICROSCOPICAL CLUB, 330 
of solid ‘‘ spokes” which dilate at the circumference into broad 
segments, which are very finely serrated on the outer margin and 
give rise to the longitudinal striation of the spine. In structure 
it approaches somewhat to Arbacia punctulata, Gray, with a sec- 
tion of a spine of which it was compared. 
Diatoms from Silt on Timber from Demerara.—Rey. Eugene 
O’Meara submitted to inspection a slide of diatoms for which he 
was indebted to the kindness of Rev. George Davidson, of Logie- 
Coldstone, near Aberdeen. The material from which it was 
prepared had been gathered by Mr. Rattray from some balks of 
timber known as “ greenheart”’ and brought from Demerara. This 
timber, when cut in the interior, is sent down the river and 
allowed to remain there until an opportunity of shipment is 
afforded, meanwhile it is covered by the silt brought down the 
river. The forms found on this slide were many of them unde- 
scribed and very beautiful. Mr. O’Meara hoped that the finders 
would take means to have these forms described in order that the 
interesting discovery should not be lost. 
Endosperm of Ricinus.—Dr. McNab exhibited a section of the 
endosperm of ficinus communis, the castor-oil seed, with a 345th 
object-glass by Gundlach. The section was placed in a mixture 
of equal parts of pure glycerine and water, which brought into 
view the numerous crystalloids which occur in the cell along with 
the oil. These are mostly octohedra, the faces, angles, and edges 
being, however, not very sharply defined. 
Spicules of Wrightella coccinea, Gray —Mr. W. M. A. Wright 
exhibited a series of spicules from the coral called by Dr. J. E. 
Gray, in his ‘Catalogue of the Stony Corals in the Collection of 
the British Museum’ (1870), Wrightella coccinea. These spe- 
cimens, given to him by Prof. E. Perceval Wright, had, like those 
in the British Museum, been collected by that gentleman in the 
Seychelles. The spicules were uf two kinds—one bacilliform with 
a few warty excrescences, the other like those called “ head- 
shaped” by Verril. Dr. Wright had informed him that he did 
not think there was any specific difference between Wrightella 
coccinea and W. chrysanthos, and that it was quite possible that 
both species were referable rather to Hllisella. 
Orystal-bearing Cells in Pandanus amaryllidifolius.—Dr. ¥. 
Perceval Wright drew attention to sections of stem of Pandanus 
amaryllidifolius, which exhibited the strings of crystal-bearing 
cells on the outside of the fibro-vascular bundles as described by 
Professor Thiselton Dyer; but in many instances Dr. Wright 
thought the sections showed these same rows of crystal-bearing 
cells occurring in the region between the epidermis and the cen- 
tral fibro-vascular bundle region. 
Spores of Elaters of Trichia turbinata, shown.—Mr. Greenwood 
Pim exhibited the spores, accompanied by the beautiful triply- 
spiral elaters, of Trichia turbinata. 
Exhibition of some of Prof. Bornet’s original Lichen-gonidia 
preparations.—Mr. W. Archer showed some preparations kindly 
