Dr Martin Barry on Fibre. 397. 
thor in a former memoir; namely, that many structures, including-blood- 
vessels, have their origin in rows of cells derived from corpuscles of the 
blood. The human spermatozoon presented a disc with a pellucid de- 
pression, each of the two sides of the peripheral portion of which was 
extended into a thread ; these two threads forming by being twisted on the 
part usually designated as the tail. The occurrence of two tails, ob- 
served by Wagner, is accounted for by the author by the untwisting of 
these threads. 
The author has noticed very curious resemblances in mould, arising 
from the decay of organic matter, to early stages in the formation of the 
most elaborate animal tissues, more particularly nerve and muscle. Flax 
has afforded satisfactory evidence of identity, not only in structure, but 
in the mode of reproduction, between animal and vegetable fibre. 
Valentin had previously stated that in plants all secondary deposits 
take place in spiral lines. In the internal structure of animals, spirals 
have heretofore seemed to be wanting, or very nearly so. Should the 
facts recorded in this memoir, however, be established by the researches 
of other investigators, the author thinks the question in future may per- 
haps be, where is the “‘ secondary deposit” in animal structure, which is 
not connected with the spiral form? The spiral in animals, as he conceives 
he has shewn, is in strictness not a secondary formation, but the most 
primary of all; and the question now is, whether it is not precisely so 
in plants? 
In a postscript the author observes, that there are states of voluntary 
muscle in which the longitudinal filaments (“ fibrillee”) have no concern 
in the production of the transverse strize ; these strize being occasioned by 
the windings of spirals, within which very minute bundles of longitudinal 
filaments are contained, and have their origin. The spirals are interlaced. 
When mature, they are flat and grooved filaments, having the compound 
structure above described. With the shortening of the longitudinal fila-. 
ments (“ fibrill”) in muscular contraction, the surrounding spirals, and 
of course the strie, become elongated and narrow; while in relaxation 
these changes are reversed. 
Dr Barry requests us to add the following, in connection with his Me- 
moir on Fibre. 
The ‘‘ white substance of the nervous fibre,” surrounding Remak’s 
** band-like axis,” consists of filaments having the remarkable structure 
above described, and often curiously interlaced with one another, as 
though each of them had a spiral direction, In examining the substance 
of the optic, olfactory, and auditory nerves, as well as that of the brain 
and spinal chord, Dr Barry employed for the most part such as had been 
preserved in spirit ; and, besides using extremely minute portions, he very 
often avoided adding any covering whatever, the weight of thin mica it- 
self being sufficient to rupture or to flatten this delicate substance, and 
thus entirely prevent its structure from being seen. In the parts last men- 
tioned, he finds red discs, which pass first into rings and then into spirals. 
VOL, XXXII. NO. LXIV.—APRIL 1842. dd 
