DUBLIN MICROSCOPICAL CLUB. 103 
and stained by Beale’s carmine solution, and drew attention to 
the fact that no nuclear structure seemed to be manifested. 
This form, which, indeed, he thought could hardly be regarded 
with the well-marked <Actinophrys sol, he had several times so 
treated, and always with the same negative result. It is a very 
inert, but at the same time a hungry form. 
17th September, 1874. 
Foraminifera from Flint-nodule-——Rev. E. O’Meara submitted 
to inspection a slide containing a great abundance of various 
species of Foraminifera found in the central cavity of a flint 
nodule from the chalk rocks in the vicinity of Belfast. He was 
indebted to the kindness of Mr. Wright, of Belfast, for the 
material, which looked like disintegrated chalk, appearing likely 
to contain Diatomaceous forms, but none were found. 
EHozéon canadense (two specimens), prepared by Dr. Carpenter 
and sent over by him for the Dublin University Museum, were 
exhibited by Professor Macalister. 
Gonium pectorale in vast numbers, forming a very pretty 
object, was shown by Mr. Crowe. 
_ Phyllactinum guttatum was shown by Mr. Greenwood Pim, 
jun. 
Structure of Spines of Echinometra lucunter.—Mr. Mackintosh 
exhibited transverse sections of spines of Hchinometra lucunter 
which appears to possess spines of two different forms. The 
greater number of them are conical and show in section the 
typical Echinometran structure, z.e. a central reticulation from 
which proceed rays, expanding at intervals into larger areas 
composed of a network with moderately wide meshes, joined 
by transverse bars going from ray to ray; the intervals oppo- 
site to the constricted part of the rays are occupied by solid 
pieces exhibiting the faint striz so common to, if not characteristic 
(?) of, these structures. The expanded portions of the rays 
become shorter and relatively wider as they approach the.cireum- 
ference, and form globular expansions just before terminating in 
two or three branches going to the notches which form the longi- 
tudinal grooves of the spine. The other form of spine is club- 
shaped, ending in a short point, and differs in structure from the 
conical ones in that the rays gradually expand for about two 
thirds of their length, then contract and end at the circumference, 
somewhat as in the other spines, short, solid, striated pieces being 
placed between their extremities. Mr. Mackintosh had sometimes 
found the same structure in spines which were more cylindrical 
than club-shaped, and required a careful inspection to distinguish 
them externally from the ordinary conical spines, and this con- 
dition appears to be the normal one in EL. oblonga. 
Structure of “ Baked” or Indurated Slate.—Professor Hull 
exhibited a thin transparent section of “baked” or indurated 
slate from the Silurian beds near Dundalk. This specimen 
