16 
G. F. Atkinson, 
Comparison witli the A manitae. 
In Amanitopsis vaginata a similar external zone of loose-meshed 
tissue is present from the early stages of the primordium of the fruit 
body, wliich completely envelops the pileus and stem primordia. The 
margin and surface of the pileus primordium in a similar way grows out 
toward this enveloping zone, the hyphae of the surface being epinastic, 
strongly so at the margin. There is no clear cut border between the 
mature pileus primordium surface and this outer zone, but many of the 
surface hyphae of the former tie into the inner surface of the latter. 
The relation of the mature pileus primordium to the enveloping zone is 
exactly the same in Amanitopsis vaginata und Agavicus. The enveloping 
zones in Amanitopsis and Agavicus are homologous structures, the “uni¬ 
versal veil” of Fries in its primordial condition. From this point, however, 
the course of development is different in the two geners. In Amanitopsis 7 ) 
a cleavage layer is formed which separates the fundament of the “universal 
veil”, or blematogen 8 ), from the pileus, forming a complete or finished 
veil, the volva, or teleoblema 9 ). In Agavicus the “universal veil”, or 
blematogen, remains concrete with the surface of the pileus, no cleavage 
layer being formed. 
Comparison with Agavicus campestvis. 
This interpretation of the “universal veil” is different from that given 
by me in the case of Agavicus campestvis in 1906 and I must confess 
that in the interpretation there given, I also have contributed to the 
confusion of the subject of the “universal veil”, or rather have assisted 
in preserving it. The very delicate, floccose weft of mycelium enveloping 
the sporophore primordium in Agavicus campestvis 10 ) I formerly inter- 
preted as the “universal veil”. It is a universal veil, but is not homo¬ 
logous with the stouter “universal veil”, present also in Agavicus cam¬ 
pestvis and homologous with the blematogen as here described. The 
outer delicate, floccose layer described in Agavicus campestvis is a primary 
“universal veil”, or protoblema 11 ). In fig. 12 this protoblem is well 
shown enveloping the young fruit bodies. The older fruit bodies show 
that it is being torn into loose floccose scales which are often quite 
distinct on the surface of the mature pileus as shown in fig. 13. This 
is perhaps what Fries refers to as “subuniversal veil” which he says 
7) A full account of the development of Amanitopsis vaginata will be published 
in anotber paper. 
8) Blematogen, or blematogen layer (ßXrj/ua = cover; yevrjg = producing), 
term proposed for tbe external zone of tissue in tbe fruit bodies of the Amanitae 
which later becomes separated from the pileus by a cleavage layer, and for the homo¬ 
logous layer in Agavicus and other genera where it remains concrete with the pileus. 
See p. 13, Atkinson, Geo. F., The development of Agavicus avvensis and A. comtulus. 
Am. Journ. Bot. 1, 3—22; pls. 1, 2, 1914. 
9) Teleoblema, or teleoblem (refaiog = complete or finished; ßb]^a = 
cover), term proposed for the complete or finished veil in the Amanitas formed through 
the Separation of the blematogen from the pileus by a cleavage layer (see p. 17, At¬ 
kinson, 1. c.). 
10) See pl. 10 and pl. 12, fig. 18, in Atkinson, Geo. F., The development 
of Agavicus campestvis. Bot. Gaz. 42, 241—264; pls. 7—12, 1906. 
11) Protoblema or protoblem (jigunog = first; ßXrjf-ia = cover). See p. 13 
in Atkinson, Geo. F., The development of Agavictis avvensis and A. 
comtulus . Am. Journ. Bot. 1 , 3—22; pls. 1, 2, 1914. 
