25 
Ordinary Meeting, November 13th, 1866. 
Edward Schunck, Ph.D., F.R.S., &c., President, 
in the Chair. 
Mr. Arthur Mc.Dougall, William Stanley Jevons, M.A., 
Professor of Logic, &c., Owens College; and William Jack, 
M. A, Professor of Natural Philosophy, Owens College, were 
elected Ordinary Members of the Society. 
“ On Echinus li vidus, illustrated by specimens from 
Roundstone,” by Thomas Alcock, M.D. 
The Author described particularly the mechanism of the 
teeth and jaws of the animal, and showed by a dissection of 
the parts that the statement made both by Professor Owen 
and Professor Rymer Jones that the striated surfaces of the 
jaws are used to comminute the food is incorrect, for the 
whole of these surfaces is occupied by muscle, and is alto- 
gether outside the pharynx through which the food passes. 
These particulars may be seen in the accompanying figure 
taken from the dissection. 
Proceedings— Lit. & Phil. Society. — Yol. VI. — No. 4 — Session 1866-7. 
