Mutinus caninus (Hud si), Fr. 349 
Intermediate tissue ( Zwischengeflecht ) of later stages. In 
reality the mass in question and the peripheral zone become 
only the outermost layer of the volva ; hence a distinction 
between the two ceases to be of importance. 
Second egg . — The next stage in the differentiation of the 
sheaf-like head N is shown in Fig. 2, with the same magni- 
fication as in the preceding figure. The egg of this stage had 
a length of about 1 mm, and a transverse diameter of \ mm. 
The general arrangement of parts is the same as in Fig. 1. 
The cortical tissue C is continued up from the mycelial strand 
and forms the outer portion of the egg. The bundle of 
medullary tissue M has about the same position as in Fig. 1, 
and can be traced as a bundle up to about the centre of the 
egg, where it branches as in Fig. 1, and becomes lost in the 
spherical mass N, lying in, and almost wholly constituting, 
the upper half of the egg. 
The peripheral portions at the upper end and sides of the 
head N have pushed outward against the cortical layer C, and 
have become differentiated into a more loosely interwoven 
structure Z, in which many of the hyphae have a radial position. 
Many of the hyphae along the inner surface of the cortical 
layer C, pass into, and take part in, the formation of the 
marginal portion of this more open structure ; still the general 
appearance of the section is such as to indicate that the 
structure is, on the whole, of medullary nature, arising from 
N. In this stage, two regions may therefore be indicated in 
the head N; the more open portion Z, just described; and 
the dense portion ^consisting of hyphae intricately interwoven 
and anastomosing, and with their nuclei at only very short 
distances apart. 
At My Fig. 2, the medullary bundle M breaks up and passes 
into the sheaf-like head N. One of the few hyphae of that 
bundle has chanced to lie in the plane of the section for 
a portion of its length after leaving the bundle. This hypha 
is designated by m. It passes obliquely upward towards the 
left, and certainly at two points gives off branches into the 
open portion Z, and is also connected on the other side with 
