The Myxomycetes of the United States. 379 



classification, based on new principles. In 1875, the more 

 elaborate, and detailed "Monografia Sluzowce" expanded and 

 illustrated his views in a complete and almost exhaustive 

 manner. 



At first Rostafinski recognized in the "Mycetozoa," as he 

 termed them, two primary divisions, in one of which the 

 spores were developed externally, on the surface of certain 

 definite spore-bearers, and in the other they were developed 

 internally, covered at first by a protective membrane or 

 sporangium. In the monograph only a passing notice is 

 given of the first division, and in the more recent "supple- 

 • ment" it is not mentioned at all. The inference to be de- 

 duced from this is that the Exosporous Mycetozoa are re- 

 garded as an encumbrance to the system, and are intended 

 to be ignored. ' 



The Mycetozoa proper being thus reduced to unity, our 

 illustrations will be understood to refer to these alone. As 

 in the Agaricini, so in the Myxomycetes, the first steps in 

 classification relate to the colour of the spores. Two sec- 

 tions include the species (1) with violet spores, and (2) 

 those having spores otherwise coloured. The Amaurosporm 

 and the Lamprosporce are the two primary sections, each of 

 which is subsequently again divided into two subsections, in 

 one of which no evident capillitium is present, and in the 

 other some kind of capillitium is alwa} f s developed. 



As the old method was based wholly on external features, 

 so the new has nearly all its essential characteristics relating 

 to internal structure. If there is any one feature in which 

 the Rostafinski method is more assailable than another, it is 

 the too slight regard which is given to external features. 

 Naturally enough, in escaping from one extreme, the rebound 

 has been to the other. Time and experience will undoubtedly 

 hereafter develop a "happy medium." 



In making use of this system, the first determination req- 

 uisite is the colour of the spores, then the presence or absence 

 of a capillitium, and finally the character of the capillitium, 



