Chap, i.] OF THE OEIGIN OF ORGANISED BEINGS. 307 



If we place the half of a given liquid in a vessel with a 

 narrow surface, and the other half in a vessel with a broad 

 surface, the proligerous pellicle of the narrow vessel is much 

 thicker than that of the broad vessel. For in the one vessel and 

 in the other has been produced an equivalent generation of 

 vibrions and of monads ; but in the broad vessel the residua have 

 been obliged to spread themselves over a larger surface. They 

 have not, for this reason, been able to form a proligerous 

 membrane sufficiently compact, and no ciliated infusorium is 

 created. 



Certainly these are very eloquent facts. A last fact let us 

 cite. There was poured into a porcelain basin with a flat bottom 

 the paste of boiling flour, about a centimetre in thickness. Then, 

 when this paste commenced to congeal, there was written on its 

 surface, with a pencil, imbibed with a strong maceration of 

 gall nut powder, previously examined in the microscope and 

 filtrated, these two words : — generatio spontanea. The basin was 

 then covered with a sheet of glass, and left to itself for four days. 

 The temperature was 24 degrees on an average, and the pression 

 0,76 during this space of time, at the end of which the words 

 generatio spontanea were seen traced in black. These characters 

 were formed by crowded tufts of a microscopic mushroom 

 absolutely unhnoum, with stalklets simple, cylindrical, not articu- 

 lated, and with capitula of a beautiful black. M. G. Pennetier 

 proposes to call this new organic species Aspergillus primigenius,^ 

 Many other topical facts can be found in the publications of F.- 

 A. Pouchet, and of his rivals MM. G. Pennetier and Mantegazza, 

 Joly and Musset, to which we must content ourselves with refer- 

 ring. The short extracts we have just given suffice to show that 

 the doctrine of spontaneous generation does not merit the vulgar 

 disdain with which it is assailed. Its partisans are able to rely 

 on serious arguments drawn from observation and experiment. 

 It is evidently not enough to oppose to them dogmatic contradic- 

 tions and some questionable chemical experiments. 

 * G. Pennetier, Origines de la Vie. 



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