Sturch . — Harvey ella mirabilis ( Schmitz & Reinke). 97 
Up to the present time the genus Harvey ella has been 
placed in the Gelidiaceae, the fourth division of the Nema- 
lionales, a position first assigned to it by Schmitz. In the 
classification of the Florideae adopted in Engler and Prantls 
£ Pflanzenfamilien V the Nemalionales are characterized by 
the gonim oblast being developed directly from the fertilized 
egg-cell. Both the Gigartinales and the Rhodymeniales 
possess an auxiliary cell placed near to the carpogonium, this 
auxiliary cell, after copulation with the egg-cell, giving rise 
to the gonimoblast : but in the Gigartinales the auxiliary cell 
is developed before the fertilization of the carpogonium, 
while in the Rhodymeniales the auxiliary cells are for the 
most part differentiated only after this fertilization. The 
genus Harveyella , which possesses an auxiliary cell developed 
before fertilization, must therefore be removed from the 
Gelidiaceae, and maybe placed in the Gigartinales. 
It is worthy of notice that in Richards’ paper on Clioreocolax 
Polysiphoniae , the typical species of the parasitic genus 
Clioreocolax 2 , it is stated that beneath the trichogyne are 
three trichophoric cells, and that the cell on which the lowest 
of the trichophoric cells rests is the 4 carpogenic cell ’ of the 
procarp. This c carpogenic cell,’ after the fertilization of the 
trichogyne, divides into a number of cells, which eventually 
give rise to the cystocarp. In the figures the carpogonial 
branch is so curved that the carpogonium, before fertilization, 
is brought near to this 4 carpogenic cell.’ This 4 carpogenic cell ’ 
is evidently, therefore, an auxiliary cell which gives rise to 
the gonimoblast. This auxiliary cell in Clioreocolax occupies 
a similar position to the auxiliary cell in Harveyella , that is, 
it is a cell of a peripheral chain, which, when the trichogyne 
is mature, is buried three or four cells deep in the frond. As 
the genus Clioreocolax consists of small parasitic Algae of 
very similar appearance, and somewhat similar structure, to 
1 Die Natiirlichen Pflanzenfamilien, A. Engler and K. Prantl, Leipzig, 1896, 
141 Lief.; Rhodophyceae, Fr. Schmitz and P. Hauptfleisch. 
2 On the Structure and Development of Choreocolax Polysiphoniae , Reinsch ; 
H. M. Richards, Proceedings of the American Academy of Arts and Sciences, 
1891. 
H 
