CHAPTER III. SPORES OF FUNGI. GERMINATION. 109 



otherwise tolerably homogeneous and transparent, contains one, or in exceptional 

 cases two or more, round and comparatively large drops of oil which are colourless 

 or coloured in shades of yellow and red according to the species, and are excentrically 

 situated ; a nucleus has been shown to be present in some cases l , and it is more than 

 probable that it is present in all. A single very long cilium arises from one point 

 of the surface. The sudden curvature of the cilium occasions a backward and 

 somewhat hopping movement of the spore often alternating with longer periods 

 of rest, especially towards the end of the stage of movement ; this stage either passes 

 directly into that of rest or, as most frequently happens, into a stage exhibiting a 

 creeping amoeboid motion, in which the cilium disappears or is dragged behind. 



According to Cornu the zoospores of Monoblepharis behave in a similar manner to 

 those of the Chytridieae. Further details and figures illustrative of these points will 

 be found below in the sections of Chapter V which deal with the Peronosporeae, 

 Saprolegnieae, and Chytridieae. 



III. GERMINATION OF SPORES. 



SECTION XXXI. Spores begin to germinate under certain necessary conditions, 

 which will be considered further on, one only being mentioned here in passing, viz. a 

 supply of Water. 



Since Prevost published his Me'moir on Caries and Ehrenberg his Epistola de 

 Mycetogenesi the germination of a great number of representatives of most of the 

 divisions of the Fungi has been observed and described. If the attempts made to 

 procure germination have not hitherto in certain cases been successful, this is partly 

 no doubt because special conditions are requisite for the purpose and these conditions 

 have not yet been ascertained ; with the study and determination of these the number 

 of failures is constantly diminishing. On the other hand, beside the spores which 

 have the power of germination, there are other cells in many species which resemble 

 the spores in origin and structure, but which so persistently withstand all attempts to 

 make them germinate that they must be considered to be incapable of germination. 

 These organs are only mentioned here in passing ; their further significance will be 

 specially noticed below in section LXX. 



The morphological process in germination consists generally in the fact that 

 phenomena of development are exhibited in the spore, which are specifically distinct 

 from those which lead to maturity. 



These phenomena may vary, either in different kinds of spores, or in the same 

 spore according to the external conditions ; for instance the recently matured 

 acrogenously formed spore (gonidium) of Phytophthora becomes the mother-cell 

 of swarm-spores in pure water containing much free oxygen ; on the contrary in 

 nutrient solutions it usually puts out germ-tubes. 



The changes in form which take place in germination group themselves naturally 

 under two heads. First, the germinating spore becomes the mother-cell of new 

 spores with or without important change of form, as in Protomyces, Phytophthora, 

 and Cladochytrium (Figs. 41, 42, 54). We may in this case speak according to 

 circumstances of spore-like spore-mother-cells or sporangia, instead of spores. This 

 would depend on the object and requirements of each occasion, without prejudice to 



1 Strasburgcr, 1. c. page 107. 



