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was particularly the case when the branch was thicker than the parent. 
Examples are shown in figs. 4 and 7. 
These thickening cushions are eminently characteristic of the species. 
Further, a wide deviation from modern fungi is seen in the tendency at 
some points to form a whorl of branches. Thus in fig. 6 a whorl of four 
branches is shown. This seems to have necessitated the formation of a 
Figs. 1-7. — Hyphse of Phycomy cites Frodinghamii. 
All hyphse are encrusted with a reddish-brown deposit of ferric oxide. 
Fig. 1. — Fragment of smaller size of hyphse. x 666. 
Fig. 2.— Fragment of larger size of hyphse. x666. 
Fig. 3. — Terminal of one of the hyphse showing rounded end. x 1333. 
Fig. 4. — Hypha showing a thicker branch arising from a thinner parent hypha. At point of 
origin of the branch, a, a cushion is developed for the support of the branch. x666. 
Fig. 5. — Same as in fig. 4, but in this case the supporting cushion is not developed. x666. 
Fig. 6. — An example of whorled branching. Four branches are shown arising from the same 
node. At a there is a protective cushion for the support of these branches, x 666. 
Fig. 7.— Branch hypha showing swellings both at the three points, a, b, and c. The swellings 
at b and c appear to have no connection with the formation of branches, x 1000. 
protective cushion at the point of union. As seen in fig. 7, swellings of 
a similar nature occurred at parts other than at the junction of threads, 
and in Plate I, fig. 2, an extreme case of this kind is shown. These have 
no connection with the formation of reproductive organs, for the latter are 
formed at the ends of the hyphse. When swellings of this kind of no 
apparent significance are observed in modern bacterial cultures, they are 
usually associated with degeneration and classed under involution forms. 
Somewhat similar swellings were found by Weiss (12) in a fossil Myco- 
rhiza from the Lower Coal Measures. These were pear-shaped swellings at, 
or apparently at, the ends of hyphse, and Williamson (13) figures and de- 
