Microscopical Society of Victoria. 
65 
aperture towards the front, a thick, hollow, blunt process, slightly 
incurved at the apex; towards the back, a more slender, longer, 
and more pointed hollow process on each side. Avicularia minute, 
situated on the two anterior processes, just under the curve. 
Front of the cell sparsely papillose, furnished with a circular 
opening having a distinctly marked border or margin, and 
immediately below a minute circular pore, best made out when 
mounted in balsam or other transparent medium. 
Back smooth, ovicells broadly galeate, papillose. The ovicelli- 
gerous cell always springs from the lower portion of a geminate 
cell, forming with it a very peculiar tricellate group. 
Habit. —Grows in small glassy tufts, about half-inch high. At 
present, only observed upon Cystophora. 
First found in August, 1879, near Spring Creek, fifteen miles 
south of Geelong. 
Catenicellopsis delicatula. n. s. Plate IY. fig. 2. 
Cells elliptically ovate, attenuated below, minutely papillose in 
front; back of the cell rounded, faintly striated ; vittse sublateral, 
short, often absent; lateral processes very small, projecting 
slightly forward, excavated below the point for a minute 
avicularium. 
Aperture nearly circular, directed partly upwards; ovicell 
smooth, ventricose. The ovicelligerous cell is the upper of two, 
which are often so amalgamated as to appear one only, 
surmounted by two slender lateral processes pointed forward. 
Habit. — Grows in tufts one and two inches high, on seaweed or 
larger forms of Catenicella . 
First found near Spring Creek in November, 1879; since 
obtained by dredging near Port Phillip Heads, and on the Back 
Beach at Sorrento. 
On Selecting and Mounting Diatoms . By W. M. Bale. 
[Head ‘27th November, 1879.J 
In the following observations, I shall endeavour to describe, as 
briefly as possible, first — the ordinary method of selecting and 
mounting diatoms, but with fuller details than are usually found 
in books, in order to suitj the requirements of beginners; and 
E 2 
