216 CHAETOPHORACEAE 
This species is so very different in form from the globose spe- 
cies of Chaetophora that one unfamiliar with it is likely to think of 
it as an abnormally fasciated Draparnaldıa. 
DOUBTFUL FORMS 
CHAETOPHORA TUBERCULOSA (Roth) Agardh, Syn. Alg. Scand. 
120 1617. Wolle, F. W. Alg: 116. M. 107.7. zr. 18857. 
Rivularia tuberculosa Roth, Neue Beitr. Bot. 1: 285. 1802 
(ref. from Cat. Bot. 3: 341. 1806). 
There has been some diversity in the interpretation of this 
species, Roth’s description, notably the clause, “ Ramis ramu- 
lisque approximatis patulis sparsis," indicates a plant differing from 
the erect-branched form illustrated by Kützing (Tab. Phyc. 3: 
pl. 19. f. or) and Hansgirg (Prod. Ale Böhm. 1: 71. ۰ 30. 
1886). These erect-branched forms correspond with our idea of 
what C. pisiformis should be. 
Kützing's earlier figure (Phyc. Gen. .او‎ ro. کر‎ 2) and European 
exsiccatae (Kitz. Ale Dec. 92.  Rabenh. Ale Eur. 7077. 
Hauck & Richter, 384. Wittr. & Nordst. 6706) seem to har- 
monize better with Roth's description, but can hardly be separated 
from tuberculose forms of C. elegans common with us. 
We should hardly wish to do away entirely with C. ۵ 
on this evidence, but we can obtain no assurance of its occurrence 
in this country, and possibly all specimens may be referred to 
C. elegans and C. pisiformis. 
CHAETOPHORA MONILIFERA Kütz. Spec. Alg. 896. 1849; Tab. 
Phyc. 3: AM. 20. f. 2. 1853.  Rabenh. Flor. Eur. Ale 3: 384. 
1868. Wolle, F. W. Ale. 118. ۸ TOF. f. 18, 19. 1887. 
The figure furnished by Wolle evidently represents only a 
zoosporiferous state of one of our ordinary species. The speci- 
men issued by Miss Tilden (Am. Alg. 9) is of no greater value; 
it does not show the large thick-walled cells to be seen in Raben- 
horst's specimen of C. monilifera. ۱ 
The suggestion of Schmidle (Hedwigia 36: 9-12. 1897), that 
this species, as well as C. pachyderma Wittr., is only a form of 
C. elegans in which the cells have largely developed into akinetes, 
appears to contain much of truth. If, however, we accept the 
view that these are only developmental forms, their names should 
