THE ANTHEUIDIA OF CHAMPIA PARVULA. 167 



and in some cases containiug chromatophores, are cut off 

 from the upper corners of the peripheral cells. 



3. Filament-cells, containing dense and highly refractive 

 protoplasm, are cut off, first from the stalk-cell, and then in 

 succession from each other, forming radiating rows of 

 filament-cells. 



4. The antheridial mother-cells are produced, singly or in 

 pairs, from the outer corners or apices of the filament-cells. 



5. The various colls which compose an antheridial cluster 

 are cut off from each other by divisions which take place 

 obliquely to the organic longitudinal axis of the cell. 



The material used in the preparation of this paper was pre- 

 served in 1% formalin. Sections were made with the micro- 

 tome, and preparations, made by crushing portions of the frond 

 upon the slide, were frequently employed. The freezing 

 microtome as described by Mr. W. J. V. Osterhout in a recent 

 paper (9) was found extremely useful. Portions of the 

 tissue of the frond were mounted in a solution of gum 

 arabic upon the freezing chamber of the microtome, frozen 

 and cut. The sections were at once transferred to the slide 

 and mounted in glycerine jelly. 



In conclusion the writer desires to acknowledge his indebt- 

 edness to Dr. W. A. Setchell who has kindly made a number 

 of valuable suggestions in connection with the preparation 

 of this paper. 



LIST OF WRITINGS REFERRED TO. 



1. Agardh, J. €J. Species Algarum. Vol. Ill, 1; p. 303. 

 1876. 



2. Farlow, W. G. Marine Algae of New England; p. 156. 

 1881. 



3. Hauck, F. Die Meeresalgen; pp. 153 and 157. 1885. 



4. Debray, F. Sur la Structure et la Developpement des 

 Chylocladia, Champia et Lomentaria. Bull Sci. de la France 

 et de la Belgique. Tom. XXIII; pp, 399—416. 1890. 



5. Webber, H. J. Note in Annals of Botany, Vol. V; 

 pp. 226—227, 1891. 



