1864. ] Samurtson on the Source of Living Organisms. 607 
My first definite evidence was obtained about three years since, when 
a series of investigations were undertaken by me in conjunction with 
Dr. Balbiani, of Paris, to whom I have already had occasion to refer 
as the author of a valuable little work on the sexual phenomena of the 
infusoria ; and it now affords me great pleasure to state that not only 
did he at that time render me very useful assistance, but he gave me 
one or two hints which led indirectly to my subsequent experiments. 
In July, 1862, I forwarded to Dr. Balbiani boluses of various organic 
substances of which I retained the counterparts, consisting of the 
green juice of cabbage (chlorophyll), and the juice of fresh and baked 
meat, variously prepared with gum-arabic, &c.; and although my 
zoological readers will find that it would be quite immaterial, in the 
form in which my experiments were conducted, whether or not the 
atmosphere was excluded from these substances, still I may mention, 
in passing, that such precautions were taken as to render it very im- 
probable that the air should reach them until they were exposed 
dissolved in distilled water. 
These infusions were examined by my colleague and myself, the 
results noted, and the contained forms delineated ; but Dr. Balbiani’s 
investigations were, in the first instance, more successful than mine, 
as he was favoured with a more elevated temperature. 
Since then I have from time to time exposed to the action of the 
atmosphere the purest distilled water that I could obtain, with a view 
to compare the living forms, if any should be present, with those 
deseribed and delineated by my coadjutor, and with any that I might 
observe in infusions that have been simultaneously exposed. 
Let us see what has been the result :— 
Amongst the illustrations first received from Dr. 
Balbiani was the accompanying, which represents 
what he called “ Cercomonas fusiformis,” found by 
him in great numbers in both the animal and 
vegetable infusions. 
Fig. 1.—Cercomonas fusiformis, 
(From Dr. Balbiani’s original drawing.) 
He designated these little forms after Dujardin, who ace 
thus figures one in his work on the Infusoria.* f= 
Dr. Balbiani might with equal propriety have called his 
animalcule, Cercomonas acuminata, also figured in Dujardin’s 
work, from which it differed but slightly, being, { think, 
the same type. 
Fic. 2.—C, fusiformis.—Duyj. 
a 
D’une infusion de mousse, grossi 500 fois.’’+ 
* ‘Histoire des Zoophytes infusoires. Paris, 1841. 
+ Let me draw the attention of my readers to the fact that, according to the 
theory of “ spontaneous generation,” this form must have been produced by the 
three totally different substances in which they were found by Balbiani and 
Dujardin. 
272 
