ch. viii.] THE BEGINNINGS OF LIFE. 429 



Yet in such menstrua as these he believes that he has found 

 even fungus-spoves " spontaneously " generated. 



The contrast here vividly brought before us draws attention 

 to what would seem to be one of the weakest points in Dr. 

 Bastian's theory. It is a long way from tartrate of ammonia 

 and phosphate of soda to the spores of a fungus. It seems 

 too long a way to be traversed in a few days or weeks amid 

 merely the simple conditions which exist within a closed 

 flask. A fungus-spore is not mere shapeless protoplasm. In 

 it, as in the bacterium and the vibrio, there is a visible 

 specialization of structure, albeit a slight specialization. 

 These infusoria are " lowest organisms," no doubt : still they 

 are really organisms and not merely masses of organic matter. 

 They have forms which are more or less persistent ; and in 

 this fact is to be seen the strongest of the objections which 

 may be urged d priori against Dr. Bastian's views. For 

 organic form is a circumstance into which heredity largely 

 enters ; and where we find organisms even so simple as the 

 jointed rods which are called vibrios, it is difficult, on 

 theoretical grounds, not to accredit them with a regular 

 organic parentage. Such considerations cannot weigh against 

 a crucial experiment ; but in the present state of the ques- 

 tion they are entitled to serious attention. Dr. Bastian argues, 

 with great ingenuity, that just as crystals, growing in a liquid 

 menstruum, take on shapes that are determined by the mutual 

 attractions and repulsions of their molecules, so do these 

 colloidal bodies, which we call monads and bacteria, arising 

 by "spontaneous generation" in liquid menstrua, take on 

 forms that are similarly determined. The analogy, however, 

 is not exact. I am not disposed to deny that the shape of a 

 bacterium, or indeed of a wasp, a fish, a dog, or a man, is 

 due, quite as much as the shape of a crystal of snow or 

 quartz, to the forces mutually exerted on each other by its 

 constituent molecules. But it must be remembered that in 

 the case of an organism, the direction of these forces depends, 



