Gi bsmithia hawaiiensis — Doty 
461 
FIGS. 3—11. Vegetative and asexual reproductive microscopic structural details of Gibsmithia hawaiiensis 
(collection No. 12343). 3, An axial filament from the medullary region of a gelatinous branch of the thallus 
showing the opposite ramification of the medullary filaments and, A , characteristic reconnecting rhizoidal 
branches. 4, A more simple reconnecting rhizoidal branch, A, from one of the subdichotomous cortical fila- 
ments. 5, A seirospore-bearing ultimate branchlet on a subdichotomous cortical filament with, A, a very simple 
reconnecting filament or rhizoid. Such lateral nonrebranched filaments, B, with a terminal series of seirospores 
were found arising from almost every second cell in the vegetative axis of this part of the filament system. 
The origins of but three such seirosporic branches are shown here. 6, A tetrasporangium-bearing cortical fila- 
ment system. Divisions within the tetrasporangia are not shown and no attempt was made to represent all pit 
connections. 7—11, Tetrasporangia in various stages of maturity. The arrangement of spores is always at first 
cruciate but, as indicated by Figure 10, in age they may not be in a strictly cruciate arrangement. 
