96 THE MYXOMYCETES. 



comparable to the last spore-bearin*,' stage of the Myxomycetes ? 

 Saville Kent answers in the affirmative, and compares it with the 

 encystment of species of Monas and Heteromita, such as has been 

 revealed by the labours of Messrs. Dallinger and Drysdale, a process 

 similar to which, according to Saville Kent's own observations, is very 

 prevalent among the Protozoa, although unknown a few years ago. 

 The chief difference is one of degree, the sporangium in the Myxomy- 

 cete being formed by the union of a vast number of amoebiform units, 

 and in the Protozoan usually by the combination of a few only. But 

 this difference is bridged over by those species with aggregated Plasmo- 

 dium, described by M. Van Tieghem (supposing them to belong really 

 to the Myxomycetes), where the sporangium is formed at times by a 

 small number of myxamcebse only.* 



The only real distinctionf between the Animal and the Vegetable 

 Kingdoms (if there be one at all) is founded upon their physiology. 

 Plants possess the power of building up organised substances out of 

 dead matter ; animals require ready organised material for their food. 

 Fungi, indeed, resemble animals in this respect, that they usually live 

 upon the nutriment already elaborated for them in vegetable cells, but 

 that they do possess the characteristic power of plants every yeast 

 cell thriving in Pasteur's solution is a living witness. The 

 Myxomycetes ingest solid particles within their protoplasm, but the 

 quantity of nutriment thus obtained must be very small, and the 

 huge masses, which are sometimes so quickly formed and in such 

 unlikely places, + must depend for their growth chiefly upon inorganic 

 material obtained from the water and the air surrounding them. 

 They are, therefore, plants. But it may be urged that, if so, many 

 monads must be plants also. This may be a "logical consequence," 

 but logical consequences have no terror for the seeker after truth. In 

 the discussion of these questions there is no room for prejudices or 

 personalities; the mind must calmly weigh the evidence, and judge 

 without fear as without favour. 



Reviewing then the whole question, we decide at once that the position 

 assigned to the Myxogastres by Fries is quite untenable. In fact, 

 nearly the whole of Berkeley's main classification (adopted in the Hand- 

 book) is now out of date, and does not represent the present state of 

 knowledge about the Fungi. Its chief recommendation is that it is 

 easy to understand and apply, but it is in many respects nearly as 

 artificial as was the system of LinnEeus in the Phanerogams. 



Saville Kent's contention also, that these organisms belong to the 

 Protozoa, is as untenable. He lays the whole stress of his argument 

 upon their mode of development, but it is usually allowed that the 

 true position of any organism is determined by the af&nities of its 



* Van Tieghem, " Bull. Soe. Bot. France," xxvii. pp. 317-22. 



i Huxley's " Science and Culture," p. 162. 



t The Myxomycetes are found usually on rotten wood or other decaying 

 substances, but thev seem to be indifferent as to the matrix on which they 

 gi-ow. One species was found on iron which had been heated only a few hours 

 before, another on a leaden tank, another on cinders. See Berkeley's " Intro- 

 duction to Cryptogamic Botany,' p. 310. 



