126 Dublin Microscopical Club. 
contents, each fraction (zoospore?) made up of one, or two, or three 
of the granules (often two larger and one of the more minute, or 
one large with two or three more minute), arranged in a tolerably 
straight file and enclosed in a proper envelope, and moving about in 
sweeps and curves or more or less straight directions, revolving the 
while on the longitudinal axis. Those who are adepts at using 3." 
or ,!' objectives might possibly discern flagella similar to those of 
Bacteria ; but nothing of the kind could be seen with ordinary powers. 
These little moving bodies ere long come to rest, and even though 
still small, not a half or a quarter of the full dimensions, become 
divided and reproduce the “* 80 ” characteristies. 
Section of Velum and Foot of Veliger larva of Purpura lapillus. 
—Professor A. C. Haddon exhibited a transverse section through the 
velum and foot of a veliger larva of Purpura lapillus, showing the 
development of the nervous system in four thickenings of. the epi- 
blast, this being the first time that the nervous system has been 
proved to have an epiblastic origin in the Prosobranchs. 
Sections of Hair-follicles stained.—Dr. J. F. Knott showed sec- 
tions of hair-follicles of human scalp perpendicular to long axis of 
hairs, stained with picro-carmine and aniline violet, which latter 
tinges the outer (Henle’s) layer of the inner root-sheath. Huxley’s 
layer staining with picro-carmine as well as the outer root-sheath, 
the various layers of the complex wall of the hair-follicles are ex- 
tremely well differentiated. Some of the specimens show with 
plainness the processes sent by the cells of Henle’s layer into the 
intercellular fenestrae of the layer of Henle. ‘This particular 
arrangement, which has been lately so graphically described by 
Professor Ranvier, formed the chief interest of the specimen. It 
accounts for the closeness of adhesion between the layers long ago 
observed, but which had previously remained unexplained. 
November 17, 1882. 
Section of Plumule of Germinating Seedling Opuntia.—Dr. M‘Nab 
exhibited sections of a plumule of a germinating seedling Opuntia. 
The punctum vegetationis was distinctly shown, with the leaves 
originating in the normal manner, the older ones having contracted 
axillary shoots bearing spines and hairs. The leaves were of very 
simple structure and outline, and possessed a single central fibro- 
vascular bundle. 
Another nondescript problematic Production.—Mr. Archer showed 
an example of a puzzling structure now and again met with in deep 
pools and amongst débris of various sorts. This is somewhat large, 
of plumply ovate figure, of brownish colour, opaque, covered by 
prominent scale-like or leaf-like seemingly imbricated projecting 
prominences—these, if he judged aright, running in spiral lines, the 
contents coarsely granular, thus the whole resembling in figure and 
