306 M. Dulrocliet on ihe Origin of Mouldiness. 



the microscope, and found it composed of branching threads and 

 articulations. He considered it as a kind of conferva. Anxious 

 to discover what might be the origin o^ this 'vegetable produc- 

 tidDj' he observed that it appeared in the «ap of the? vih6 Avheri 

 collected \in vessels, and that in then^ it developed 'itself with 

 rapidity* jHe.was thus led to consider this vegetable produc- 

 tion a^ owing it^ origin to a tendency which the sap of the vine 

 had t6 become organized, consequently as being the result of a 

 spontaneous generation. Starting with this supposition, M. 

 Amici is led to allow that it is by means of this tendency to spon- 

 taneous organization, that in general the sap produces wood, the 

 increase of which it is continually effecting. Passing by this hy- 

 pothesis, I wish to discover the class, and the conditions in which 

 this kind of vegetable filament exhibits itself, and of which M. 

 Amici only discovered a single variety. For the most part they 

 present themselves under the appearance of a white or rather 

 transparent kitid of felt, composed of 'a number of branching 

 filaments of the minutest delicacy ; they never exhibit the green 

 colour peculiar to the confervas and to the vaucheriae. Besides, 

 these vegetable filaments which we are now considering, do not 

 require the influence of the light that they may live and thrive; 

 th^y grow as' wdl in the dark as in the light. They are seen to 

 grow in water containing certain organic matters. I have seen, 

 as M. Amici did^ their development in the sap of the vine, also in 

 guiio water ; but they especially appear in abundance in water 

 in which a little isinglass is dissolved. In water, which holds 

 ifi solution a small <5uantity of the gelatine of strong glue, they do 

 not appear so frequently ; and when the water holds in solution 

 a little albumen from the egg^ they do not appear at all. lam 

 quite satisfied of this last fact from the many experiments which 

 I have made. And this fact will presently be of use when in- 

 vestigating the conditions under the dominion of which these in- 

 fusores vegetables appear. We must first, however, determine 

 their nature. 



The vegetable filaments which we are here considering, ex- 

 hibit themselves, as I have just said, under the appearance of a 

 kind of felt, composed of branching threads. It is especially at 

 the bottom of the vessel, which contains the liquid in which they 

 appear, that they accumulate ^w^jilst we very frequently observe 



