POLYMORPHISM. 207 



interested observer to this effect. " On a preparation preserved 

 in a moist chamber, on the third day a white speck -was seen on 

 the surface, consisting of innumerable ' yeast ' cells, with some 

 filaments, branching in all directions. On the fourth day tufts 

 of Penicillium had developed two varieties — P. glaucum and 

 P. viride. This continued until the ninth day, when a few of 

 the filaments springing up in the midst of the Penicillium were 

 tipped with a dewdrop-like dilatation, excessively delicate — a 

 mere distended pellicle. In some cases they seemed to be 

 derived from the same filament as others bearing the ordinary 

 branching spores of Penicillium, but of this I could not be 

 positive. This kind of fructification increased rapidly, and on 

 the fourteenth day spores bad undoubtedly developed within the 

 pellicle, just as had been observed in a previous cultivation, 

 precisely similar revolving movements being also manifested."* 

 Although we have here another instance of Mucor and Penicillium 

 growing in contact, the evidence is insufficient to warrant more 

 than a suspicion of their identity, inasmuch as the equally 

 minute spores of -Mucor and Penicillium might have mingled, 

 and each producing its kind, no relationship whatever have 

 existed between them, except their development from the same 

 matrix. 



Another case of association — for the evidence does not proceed 

 further — was recorded by us, in which a dark-coloured species 

 of Penicillium was closely associated with what we now believe 

 to be a species of Macrosporium — but then designated a Spo- 

 ridesmium — and a minute Sphceria growing in succession on 

 damp wall-paper. Association is all that the facts warrant us 

 in calling it. 



We cannot forbear alluding to one of the species of Sphmria 

 to which Tulasne f attributes a variety of forms of fruit, and we 

 do so here because we think that a circumstance so extraordi- 

 nary should be confirmed before it is accepted as absolutely true. 

 This refers to the common Sphceria found on herbaceous plants, 



* Lewis's "Report oa Microscopic Objects found in Cholera Evacuations," 

 Calcutta, 1870. 



+ Tulasne, "Sclecta Fungorum Carpologia," ii, p. 261. 



