344 
peritoneal epithelium. In short, there is no reason why the 
cells spoken of as forming endothelium should have a common 
title, distinct from the general term epithelium. 
The introduction of the new term is really a step backwards 
from, instead of an advance beyond, the old classification given 
in Quain’s Elements of Anatomy, where epithelium is divided 
either physiologically into epidermic, mucous, glandular, vascu- 
lar, serous, &¢., &c., or structurally, into columnar, spheroidal, 
ciliated, tesselated, squamous, &c., &. Some such nomencla- 
ture as this satisfies all requirements, either morphological or 
physiological. The chief morphological importance, as far as 
our knowledge goes, attaches itself to the question, from which 
of the three primary layers, epiblast, hypoblast, or mesoblast, 
any given epithelium is derived ; for physiological purposes, all 
we need is some system of phrases which shall clearly indicate 
the individual characters and the arrangement of any group of 
cells; and these requirements are met by the phrases enume- 
rated above. We do perhaps want easy terms denoting whether 
the epithelium in any spot consists of several layers, or of one 
pronounced layer only; monoderic may be proposed for the 
latter, polyderic for the former case. Epithelium itself would 
only mean cells lining a cavity or coating a free surface. 
(2) On some Problems on the Physiology of Nutrition, 
and the methods of solving them. By Dr Micuazu 
Foster. 
(3) On an Experiment of Galileo. By Mr SrpiEy 
TAYLOR. 
Mr Sedley Taylor drew attention to an observation made 
by Galileo, and described by him in the first of his Dalogha 
delle nuove scienze’. Galileo says that while scraping a brass 
1 Vol. x11. pp. 104, 105, of the Florentine edition of Galileo’s complete works. 
ee 
