374 
NOTES AND MEMORANDA. 
most effectual thing for cutting off the supply of germs into that limb, 
if germs really do enter it. Thereby, I ought to stop decomposition 
of that limb, for I have cut otf both oxygen and blood from it. 
Nevertheless, the muscles of the limb will of a certainty decompose. 
My explanation why the limb decomposes, under those circumstances, 
is clear enough. I would say that I have left the water of the tissue 
subjected to agents in the blood itself, fibrine, and blood-cells, which 
are alone suf&cient to decompose the water of the tissues, and that as 
I have cut off the supply of blood that was entering the limb, the 
liberated hydrogen, in the nascent state, combines with the nitrogen 
and other elements of the nitrogenous textures, and sets up the series 
of decompositions — or re-compositions — called putrefactive changes. 
Is there, then, no truth at all in the germ hypothesis ? There is, 
I think, a germ of truth. I believe it is probable, from the two 
circumstances, that filtration of air does, in some structures, check 
putrefactive change, and that in these instances new forms of life are 
developed. From these two circumstances it is, I repeat, probable 
that there may exist in the air minute organic particles which, coming 
into contact with the water of collodial structures and fluids, are 
capable, like fibrine and blood-cells, of starting the decomposition of 
water, and so exciting putrefaction. Germinal particles may thus 
be added to other and much more abundant materials capable of 
exciting the change. This is all I have to say, from what I have 
seen, in support of the germ hyjmthesis; and indeed, in saying so 
much I am rather acknowledging certain facts which, at this moment, 
do not admit of other explanation, than putting forth an affirmative 
opinion.* 
“ ffullite .” — At the Dublin Meeting of the British Association, 
Mr. E. T. Hardman, F.C.S., read a paper on this hitherto undescribed 
mineral, which occurs in abundance near Belfast, in the basalt form- 
ing the neck of a Miocene volcano. The author proposed to call it 
Hullite, after Professor Hull, in commemoration of the valuable work 
he has done in elucidating the microscopic mineralogy of the basalts 
of Ireland. Professor Hull has examined the microscopic structure of 
the mineral and of the rock in which it occurs, and has described the 
appearance presented by the mineral. Under the microscoj^e it is of 
an amber-brown colour, nearly opaque. It permeates the whole rock, 
filling the interstices, and enclosing the other minerals. It appears 
very much to assume the character of chlorite, and is undoubtedly a 
distinct mineral, and not a product of alteration. 
The Bevivijication of Diatoms . — Eeferring to the communication of 
M. Petit (see p. 26) to the French Botanical Society, M. Bureau 
reminded the Society that some plants relatively higli in organization, 
such as certain species of Selaginella and Ferns, were capable of being 
revivified after a prolonged desiccation in an oven heated to 60° C. 
He had made experiments which left no doubt on the subject. 
M. Duchartre observed that a distinction must be made between 
the experiments of M. Bureau and those of M. Petit on the Diatomaceae. 
It appeared to him, according to M. Petit's communication, that it is 
* ‘Journal of the Society of Arts,’ vol. xxvi. p. 971. 
