146 ULOTHRICAEAE 
times not completely encircling the cell), enclosing one to several 
pyrenoids. 
Asexual reproduction by means of zoöspores, formed to the 
number of 1-4 in any cell; they are 4-ciliate, furnished with a 
red eyespot, and germinate immediately, forming a holdfast. 
Akinetes are also formed. 
Sexual reproduction through conjugation of biciliate gametes 
of which 8 or more may be formed ina ce 
Inhabitants of fresh and salt water. Type, U. ۵ 
Kitz. [Etym. oddo¢, crisped, and 402, hair. | 
European algologists like Hansgirg and DeToni, who have con- 
tended for the prevalence of Hormiscia over Ulothrix on the 
ground of priority, appear to have overlooked the real date of 
Ulothrix. It is referred to by Kützing himself in the Species Al- 
garum as founded on U. tenuissima Kitz. Alg. Dec. 744. 1836. 
Actually, the genus was founded three years earlier by the de- 
scription of this species as the type (7. ¢., the first in order), and 
the addition of well-known Conferva species, notably C. zonata 
Web. & Mohr. Unquestionably, then, Ulothrix has the claim of 
priority over Hormiscia Fries, 1835. 
As a matter of fact the two genera should never have been 
treated as synonymous, for Hormiscia originally included only Coz- 
ferva penicilliformis Roth and C. Wormskioldii Flor. Dan., both of 
which have recently been acknowledged to belong to Urospora 
Aresch. rather than to Ulothrix. Rabenhorst (47) at first em- 
ployed Hormiscia in its correct, restricted sense; but in his final 
work (Flora Europaea Algarum) he adopted the erroneously en- 
larged sense of Areschoug (’66), who had placed with 0 
penicilliformis (Roth) Fries, Ulothrix zonata (Web. & Mohr) Kütz., 
a species which never belonged in such an affinity. At the same 
time Areschoug had established a new genus Urospora on a sup- 
posed new species U. mirabilis. In 1874 Areschoug discovered 
that his Urospora mirabilis was identical with Hormiscia penicilli- 
formis (Roth) Fries, but instead of reducing his genus Urospora 
to synonymy, as he should have done, he created the new com- 
bination Urospora penicilliformis. 
The fact that Hormiscia has been recently employed in the 
incorrect sense inaugurated by Areschoug and continued by 
Rabenhorst, does not militate against the necessity of reviving it 
