Atio'. 15. ig;^] 



NAT [/US 



30 r 



scries of these changes occupied about ten days. In other 

 cases similar corpuscles developed into fungi ; while in 

 some instinces in the same pellicle the change into 

 Amceb;i; on the one hand, and into Fungus germs on the 

 other, went on simultaneously. It was soon discovered 

 that the temperature at which the infusion was made was 

 of great importance. If it had been heated to 212° F. no 

 development beyond Bacteria occurred ; if at 149° — 158° F. 



fungus germs arose ; while an infusion in all other re - 

 spects similar, but prepared at a temperature of 120° — 130' 

 F. gave rise to actively-moving Monads. 



A step further takes us to the " spontaneous eggs " of 

 Pouchet, which are seen to be formed in the pellicle, and 

 afterwards give birth to Paramecia — highly organised 

 ciliated Infusoria. These never appear except in infusions 

 made with cold water, and Dr. Bastian assures us that he 



Development op Ciliated Infusoria— (>; 600). 



Fig. 5.— Modes op Origin 

 A transforming Eugleaa with red "eye spsck" still visible. /• Asimibrbody, having many of 

 almost motionless cilia, c. A completely decolourised sphere derived from a transformed Euglei 

 d, e. More advanced forms of a similar embryo developia^:; into a Dileptas(?). /. Vorticella, soon 

 which subsequently develops into a striated variety (g). h. A large Chlorococcus-v 

 at last become converted into an animalised mass (i), which gradually shapes itself 



ts chlorophyll corpuscles still green, fringed with 

 a, provided with a few partly motionless cilia, 

 fter its emergence from a cyst of Euglena origin, 

 ttents gradually undergo decolourisation (y), and 

 the form of an Oxytricha (/) : this after a time ruptun 



A form of Plasconia derived from an embryo produced within other apparently simila 



Fig. 6. — Origin op Nematoids from Euglen.« (Gros). 

 A large Euglena which after encystment has undergone fission, whilst one of the halves has become decolourised, b. An Euglena which has become 

 converted mto a decolourised embryonic mass, leaving only a small coloured remainder, e. Another decolourised mass, which, after undergoing 

 certain changes, becomes converted into a young Neinatoid, as at ^^d). e, A female specimen of the developed Nematoid three weeks old, in whose 

 1 partially developed ova are seen. 



has verified Pouchet's observations in all essential par- 

 ticulars, as represented in Fig. 6 ; and the still more 

 complex Vorticelte have been seen to arise in a simdar 

 manner. Now the germs of Ciliated Infusoria are com- 

 paratively very large and easily recognisable ; they have 

 never, or very rarely, been discovered in the atmosphere ; 

 and no competent observer could overlook them ; so that 

 it is almost impossible not to accept the fact of the origin 

 of these organisms in the manner here described. 



The course of the argument is at this point interrupted 

 by a chapter on the Atmospheric Germ Theory, which, 

 though exceedingly interesting and well written, is quite 

 out of place here ; and we then come to some curious 



observations on the production of organisms within the 

 closed cells of various plants. M. Trecul, a distinguished 

 French botanist, has watched the formation of Amylobac- 

 ters, low organism allied to Bacteria, and minute Fungi 

 within the closed cells of living plants. In Ficus carica 

 he discovered fungoid organisms within the completely 

 closed cells of the medullary tissue, which, he believes, 

 "negatives all ideas as to the introduction of germs from 

 without." Minute ci7stalline tetrahedrons in cells of the 

 bark of common elder and other plants were actually seen 

 to be transformed into Amylobacters. The transforma- 

 tion of milk globules and a film of diluted cream-cheese 

 into Fungusgerms has also been closely watched by several 



