266 Dar bishire . — On Actinococcus and Phyllophora . 
enters through the ostiole of the small antheridial cavities. 
The intramatrical portion consists of longish cells in uni- 
serial filaments, which branch in the medullary tissue of 
the host, forcing their way along the middle lamellae of the 
cells. The extramatrical portion is formed by filaments 
arising from the intramatrical tissue which break through 
the cortex and give rise, on the external surface of Phyllo- 
phora , to a parasitic cushion of radially disposed rows of 
cells, which eventually develop into tetrasporangia. The 
outer and innermost cells of these fertile filaments remain 
sterile. The tetraspores are formed by cruciate division. 
Antheridia and procarpia are unknown. It is also not yet 
known what becomes of the tetraspores, and whether the 
spores which give rise to the parasitic nemathecia on Phyll. 
Brodiaei (Turn.) J. Ag. are tetraspores or carpospores. 
In conclusion I have to express my thanks to the ‘ Kgl. 
Ministerial-Kommission z. Untersuchung d. deutsch, Meere 
in Kiel ’ for permission to make use of the cliches for the 
illustrations in the text of this paper. 
Literature. 
1 . Darbishire, O. V. : Beitrag zur Anatomie und Entwickelungsgeschichte von 
Phyllophora: Bot. Centralblatt, Band 57, n. 12, 1894. 
2 . Darbishire, O. V. : Die Phyllophora-Arten der westlichen Ostsee deutschen 
Antheils : Wissenschaft. Meeresunters. herausgegeb. v. d. Kora. z. 
Unters. d. deutsch. Meere in Kiel, u. d. biolog. Anstalt a. Helgoland. 
Neue Folge, Band 1, Kiel, 1895. 
3 . Gomont, M. : Note sur un memoire recent de M. F. Schmitz intitule, ‘Die 
Gattung Actinococcus Ktz.’ : Journal de Botanique, no. du i er Avril, 
1894. 
4 . Kolderup Rosenvinge, L. : Deuxieme memoire sur les Algues marines du 
Groenland : Meddelelser om Groenland, XX, Copenhague, 1898. 
5 . Schmitz, Fr. : Die Gattung Actinococcus Kiitz. : Flora od. Allgem. Botan. 
Ztg., Heft 5, 1893. 
