RicE: INTERNAL SORI OF PUCCINIA SORGHI 45 
bearing spores of all sizes and shapes (Fics. 3, 4). The surround- 
ing cells are distorted by the hypertrophy of the enclosed cell 
and by the abundant intercellular mycelium but many of them 
still show nuclei. Often the large nuclei are indented by haus- 
toria. 
A third case was in a stem—one of the upper internodes— 
which developed infection from a surface inoculation between 
sheath and stem. The sections showed a heavy infection in the 
cortex underlying a mature teleutosorus bordered by two young 
sori just breaking the epidermis. At the depth of the second 
vascular-bundle-circle an internal sorus lies in the parenchyma 
between two bundles. The cells are in some cases fairly complete 
and show triangular, intercellular spaces but they are encroached 
upon and broken by hyphae from the intercellular spaces. The 
largest pocket had been formed by the breaking down of several 
cells as shown by incomplete remaining partitions. The central 
space is crowded with angular abnormal spores so incompletely 
developed by reason of pressure that their identification as 
teleutospores is doubtful. 
Internal teleutosori were found also, as noted, in the tissue of 
an abnormal branching ear which had been artificially infected. 
Cuts from the succulent tissue showed to the naked eye brown 
spots in the white tissue. The sections showed a thin-walled 
parenchyma tissue with a mesh of slender hyphae in all the inter- 
cellular spaces, and the characteristic two-lobed haustoria 
extending into the cells to the vicinity of the nuclei. Under 
the external teleutosorus, just within the circle of bundles, pock- 
ets occur formed of enlarged broken cells and meshes of hyphae. 
The hyphae generally enter from the corners of the cells and 
form tufts of branches bearing irregular, unevenly developed 
teleutospores. 
n the teleutospore cysts, particularly in those of the first 
case described, one is impressed by the many parallel hyphal 
strands both within and without the. host cell walls which thus 
form a pseudo-parenchymatous capsule for the spores. Such 
encystment within the cells has not been described by others. 
There is evidence, I believe, of the same tendencies which lead 
to the formation of a mass of hyphae at the base of a normal 
sorus rather than of adaptation such as is seen by Bolley in the 
case of subepidermal rusts. The phenomenon of subepidermal 
