A Monograph of the Mii.rogastreif. 29 



ITymcnogastcr, where the spores are liberated only by tlie decay 

 of the plant without any apjoarent morphological provision for 

 their dispersion, we trace, as the above ground genera appear, 

 the gradual evolution of the capillitium through such genera as 

 Diploderma and Scleroderma, until in Lycopcrdon we find the 

 highly specialized hyphae forming the capillitium effecting at 

 maturity the rupture of the peridium, and consequent disper- 

 sion of the spores. This phase is the most perfect, so long as 

 dispersion is effected by mechanical methods, but in the Phal- 

 loidcae we find the mechanical method superseded by a totally 

 different idea ; brilliant colours, usually combined with a strong 

 odour, and the presence of a sweet substance, bid for the visits 

 of insects, which in return disperse the spores. In the Myxo- 

 gastres the mechanical method of spore dispersion is the most 

 perfect condition attained, as illustrated by the rough, elastic 

 capillitium of many species of Arcyria. The above allusion 

 must not be interpreted as implying relationship between the 

 Gastromycetes and the Myxogastres ; in fact I see in this point 

 of agreement no more proof of affinity than exists between the 

 Pballoideae and those flowering plants that make use of the 

 same announcements to insects, in the form of colour, scent, and 

 honey in connection with pollination. I consider the Myxogas- 

 tres as illustrating one of the earliest known attempts at 

 differentiation in the direction that has eventually resulted in 

 the mass of organisms constituting the vegetable kingdom, but 

 having originated from the Flagellatae, a group more in touch 

 with the animal side of life, the work of developing individuality 

 has been slow, as illustrated by the tardy appearance of cellu- 

 lose cell-walls, which, as would be expected, is most complete in 

 the newly evolved reproductive phase, itself to a great extent 

 the outcome of a gradual change of environment from aquatic to 

 aerial — but the radical mistake, after having adopted the plant 

 line of development, consisted in the non-development of chro- 

 matophores, and retention of the animal mode of nutrition, 

 which in the plant world means parasite or saprophyte. The 

 fungi, a later group, differentiated from ancestors that had 

 already evolved the leading plant characteristics, including cell- 



