194 CHARA AUSTRALES ET ANTARCTICA, 
with a very inconspicuous one, as may be seen in Chara Drummondi. 
On the other hand, in many of those species, the superior whorls, which 
contain the fructification, are covered with a jelly, pellucid and very 
slimy, as is expressly noted in the manuscript communications of 
Mr. Drummond to Sir W. Hooker. In general I cannot help paying 
my tribute of admiration to the perspicacity and carefulness of Mr. 
Drummond in collecting these minute and difficult plants, the species of 
which, as well as the mostly separated sexes, he exactly distinguished, 
and even took the pains to detect germinating specimens of several 
of them 
In fern to the generic division of Characee, I remark, that I have 
found a sufficient character to distinguish the two genera of Niżella and 
Chara, originally founded only on the habit. This character consists in 
the construction of the stigma, or rather the coronula of the seed, which 
is formed by the summits of the five involucral leaves spirally involving 
the spores, and constituting the striated seed-vessel. This coronula 
consists, in the genus Chara, of five cells, which form a simple circle, 
and sometimes spread themselves in the form of a star; while, in the 
genus Nitella, the coronula consists of ten e forming two circles 
one lying above the other, and never sprea esides, zx coro- 
nula of Chara is persistent, that of Nitella Polar falling ff before 
the complete maturation of the seeds. The character on which on genera 
Chara and Nitella were founded by Agardh, consisting in the coated 
(striated) or uncoated stems is not universally available: all Nited/as, 
indeed, have uncoated stems; but all Charas have not coated stems. 
Each of these genera may be divided in two subgenera, according to 
the position of the antheridia or globules. In most of the Nitelle 
they are terminal, that is, situated on the summit of the chief ray of 
the leaves (branches of the whorl), in the midst of the secondary rays, 
which form the furcated division of the leaf. This is the case in the 
true Nitelle, N. flexilis, syncarpa, translucens, gracilis, tenuissima, &c. 
In some other species, as W. nidifica and fasciculata, the antheridia are 
placed laterally on the joints of the articulated chief ray of the leaves, 
between the lateral rays, which never attain the length of the chief ray. 
This subgenus I call 7o/ypella. 
The genus Chara may be divided into Chara, in the stricter sense, in 
which the antheridium takes the place of one of the little foliola (com- 
monly called bractez). In the monecious species of this division 
