394 
PHYSIOLOGY. 
BOOK II. 
description of tissue that the phenomenon of cyclosis takes 
place. The detailed statements of Professor Schultz of 
Berlin, to whom, almost exclusively, we owe all that we 
know with precision concerning this important discovery, 
w^ere communicated to the Academy of Sciences of Paris, in 
September, 1829; they were reported upon in September, 
1830, by Messrs. Cassini and Mirbel, with a recommendation 
that the memoir, and the beautiful drawings accompanying 
it, should be published. This, however, was not done, but, 
in the year 1833, the great Montyon prize in physics was 
awarded to M. Schultz, for a new memoir upon cyclosis, 
upon the report of Messrs. Auguste de St. Hilaire, Dutrochet, 
Adr. de Jussieu, Becquerel, and De Mirbel. Owing, how- 
ever, to some unexplained cause, the memoir is still, March, 
1839, unpublished, although its appearance is said to be 
close at hand. Under these disadvantageous circumstances, 
it is not surprising that so many errors should have been 
committed concerning cyclosis: some, among whom 1 am 
to be numbered, doubting its existence as a peculiar system 
of motion ; most writers confounding it with rotation ; and a 
few describing it, but, according to its discoverer, with but 
little attention to precision. I confess that, until I enjoyed 
the advantage of examining it with Professor Morren and 
Professor Schultz himself, I had no exact ideas concerning 
it. In the following statement, I have endeavoured to con- 
fine myself to the explanations given by Professor Schultz 
himself, with one or two exceptions. 
1. The phenomenon of cyclosis consists of a motion of fluid 
called latex^ usually more or less milky, but often transparent, 
which conveys granular matter through a plexus of reticu- 
lated vessels, in all directions ; when the vessels are parallel 
and near each other, the currents rise in some and fall in 
others, but, in connecting or lateral vessels, the currents are 
directed from right to left, or the reverse, according to no 
apparent rule. The contiguous rows of vessels anastomose 
from place to place ; which produces a permanent interrup- 
tion of the rising and falling currents. In order to enable a 
circulating motion to take place, it is necessary that the 
system of vessels should be reticulated, as takes place in the 
