128 Massee. — A Revision of the 
known respectively as the primary or universal veil, and 
the secondary veil, which are most perfect in the highest 
stage, and entirely absent from the lowest. 
The Agaricineae do not form a single group having the 
sequence indicated, but are in reality broken up into four 
groups or series, each running through the five types of 
structure already explained. These four groups are charac- 
terized by the colour of the spores, as follows : spores black — 
Melanosporae ; spores brown — Ochrosporae ; spores pink 
or salmon-colour — Rhodosporae ; and spores white — Leuco- 
spore. These four colour-groups form a sequence of develop- 
ment in time, the Melanosporae being the oldest, and the 
Leucosporae the newest. The evidence in support of this 
statement is as follows. In the oldest group, omitting 
Coprinns , which it has hitherto included, the five types of 
structure are not represented at the present day, types i and 
2 being obsolete ; the species are few in number and of 
world-wide distribution ; the sporophore is very short-lived, 
and entirely lacks the differentiation of structure present in 
the tissues of the higher groups ; the primary and secondary 
veils, when present, are comparatively rudimentary, and the 
spores are relatively large. 
Passing to the newest group in time, the Leucosporae, we 
find the species more numerous than those of the three 
older groups added together ; and although representatives 
are met with everywhere, the different sections and genera 
are highly characteristic of special regions. All the five 
types of structure have representatives, the simplest types 
having fewest species ; the sporophore in the highest forms 
is fleshy, and persists for several days, producing spores in 
succession, thus extending the period of spore-production, and 
in proportion the extension of the species in space. In some 
genera the sporophore is corky and persistent, and from 
analogy with what occurs in other groups of Fungi, as the 
Polyporeae, may become perennial. The primary and 
secondary veils are highly developed, and afford complete 
protection to the hymenium until the spores are mature. 
