Spontaneous Vitality of Microscopic Animals. g 



The green vegetable matter of Dr. Priestley, which is universally 

 produced in stagnant water, and the mucor, or mouldiness, which is 

 seen on the surface of all putrid vegetable and animal matter, have 

 probably no parents, but a spontaneous origin from the congress of the 

 decomposing organic particles, and afterwards propagate themselves. 

 Some other fungi, as those growing in close wine-vaults, or others 

 which arise from decaying trees, or rotten timber, may perhaps be 

 owing to a similar spontaneous pi'oduction, and not previously exist 

 as perfect organic beings in the juices of the wood, as some have 

 supposed. In the same manner it would seem, that the common escu- 

 lent mushroom is produced from horse dung at any time and in any 

 place, as is the common practice of many gardiners; Kennedy on 

 Gardening. 



Appendix. 



THE knowledge of microscopic animals is still in its infancy: those 

 already known are arranged by Mr. Muller into the following classes; 

 but it is probable, that many more classes, as well as innumerable 

 individuals, may be discovered by improvements of the microscope, as 

 Mr. Herschell has discovered so many thousand stars, which were 

 before invisible, by improvements of the telescope. 



Mr. Muller's classes consist of 



I. Such as have no External Organs. 



1. Monas: Punctiformis. A mere point 



2. Proteus: Mutabilis. Mutable. 



3. Volvox: Sprucricum. Spherical. 



4. Enchelis: Cylindracea. Cylindrical. 

 .5. Vibrio: Elongatum. Long. 



* Membranaceous. 



6. Cyclidium : Ovale. Oval. 



7. Paramecium: Oblongum. Oblong. 



8. Kolpoda: Sinuatum. Sinuous. 



9. Gonium: Angulatum. With angles, 

 10. Bursaria. Hollow like a purse. 



C 



