NATURAL HISTORY. 
AtrRA.) This appears like small black dots on 
the surfaces of marine rocks. 
DIVISION 2, CONFERVOIDEZ. 
The plants of this division have tubular jointed 
Sronds, and the fructification consists of minute spo- 
rules within the articulations. 
DRAPARNALDIA. 
The frond gelatinous—the primary filaments bear 
ing penicellate fuscicled branchlets, 
1. D. Gromerata. E, Bot.t. 1740. (Con- 
FERVA MUTABILIS.) 
2. D. Puvumosa. Dillwyn, t. 12. (Conr. 
Movrasitis.) Both these species are frequent 
in clear streams and ditches, attached to marine 
plants. 
ZYGNEMA. 
The filaments gelatinous, simple and equal, uniting 
in pairs by means of lateral tubes—the sporules dis- 
posed in a spiral or stellate manner, 
1, Z. GeEnurtexa. E. Bot. t. 1914. (Conr. 
GENUFLEXA.) 
2. Z. Deciminum. Dillw. t.4 and 5, (Conr. 
Nitipa & JuGaLis.) E, Bot. t. 2339. (C. 
NiTIDA.) 
