LIFE HISTORY OF CORALLINA OFFICINALIS 
VAR. MEDITERRANEA* 
S. YAMANOUCHI 
The group of red seaweeds known as the Cryptonemiales 
includes many species displaying a wide variety of form. The 
structure of the reproductive organs and the mode of reproduction 
found in this group cannot be ascertained adequately by the study 
of a single species. In order to distinguish the Cryptonemiales 
from the other groups of Florideae, the method of reproduction, as 
existing in Dudresnaya, has constantly been cited as characteristic 
and representative of the entire group; but it is merely charac- 
teristic of that genus. Moreover, our present knowledge of 
Dudresnaya is confined to its morphological features. In any 
systematic arrangement of the forms belonging to the ill-defined 
Cryptonemiales, Corallina should always be placed near the summit. 
This does not mean, however, that the structure of the reproductive 
organs and the mode of reproduction are more complicated than 
in other forms belonging to this group. About 30 years ago, 
Sotms-LAUBACH published his original work on the structure of 
Corallina, but no cytological work was attempted, and the life 
history of the plant was not established. Consequently, a cyto- 
logical study of Corallina was made from material secured at the 
Bay of Naples, Italy. 
Origin of conceptacle 
Generally the conceptacles are formed at the ends of branches 
of the thallus. The reproductive organs, which arise within the 
conceptacles, originate from these so-called disk cells which com- 
pose the central portion of the growing apex of each branch. The 
disk cells located at the periphery continue to divide and grow up 
around the reproductive organs, leaving only a small aperture or 
ostiole at the apex, thus forming the conceptacle. The three kinds 
* Translated by CLARENCE C. BAUSMAN, assisted by C. Cursa, from Bot. Mag. 
Tokyo 27:279-285. figs. 1-8. 1913. 
Botanical Gazette, vol. 72] [90 
