NORTH AMERICAN ANTHURUS 



401 



gleba, and the gelatinous layer of the peridium, are direct continuations of the medullary 

 tissue of the mycelial strand and must be regarded as of medullary origin. The inner 

 wall of the peridium has the same origin probably on account of its subhymenial 

 connections. 



The cortical tissue of the mycelial strand is continued in the thin outer layer of 

 the egg (C, Figs. 14 and 16). The hyphae of this layer have become more irregular 

 in form, and branch and change their course so as to become extremely interwoven. 

 The tissue remains loose, and must allow circulation of air throughout its whole extent. 

 By referring to the cross section (Fig. 16), portions C of the cortical tissue may be 

 seen extending inward from the main peripheral mass of this tissue to the gleba. 

 There are six of these portions placed at about equal distances apart in the cross 

 section. They have the position of walls or plates extending from the base of the egg 

 longitudinally upward to a short distance above the gleba mass, and extending inward 

 from the peripheral layer to the fundament of the stipe and arms. In all of the lower 

 and middle portions of the egg, these plates of cortical tissue divide the gelatinous layer 

 M' into six parts, the hyphae of which do not cross through the partition from any part 

 into the adjacent one. The partitions do not extend to the apex of the egg — at least 

 not in this nor in the more advanced stages which I have examined. Above the level 

 of the upper ends of the arms, the portions extend inward from the cortex only a part 

 of the distance to the axis, and the amount of this inward extent diminishes rapidly 

 higher up, so that near the apex of the egg the partitions become so shallow as to be 

 hardly more than traces along the inner face of the cortical layer. It follows from 

 this that in the upper part of the egg, there is but a single mass of the gelatinous 

 layer M' and that this is divided below by the cortical partitions into the six masses 

 already mentioned. 



In the lower third of the egg, there is a cylindrical layer of tissue (C", Figs. 14 and 

 15) similar to that of the partitions and into which they pass. This layer completely sur- 

 rounds the fundament of the stipe and wholly separates it from the gelatinous layer of the 

 peridium. Toward the inner face of the layer C", its hyphae anastomose less frequently 

 and are less branched, but become closely and irregularly laterally inflated. In preparations 

 stained with paracarmine alone, the walls of these hyphae were but slightly stained as 

 compared with their protoplasmic contents. In such preparations the greater masses of 

 protoplasm at the inflated portions gave to the hyphae a dotted look under low and medium 

 magnification (p, Figs. 14 and 15). In the double-stained preparations with the cell-walls 

 well brought out, these hyphae appeared under high magnification as shown in x and x', 

 Fig. 18. 



