322 IMIOTOCOCCBÆ. HÆMATOCOCCUS., 323
repeated, and hence arise so many concentric vesicles enclosing
the small globule in the centre.
“ Frequently the globule, having shrunk from its proper
envelope, is divided into half, and each half, having shrunk
from its investing vesicle, again is divided into two parts, and
this occurs many times in succession. A t length, the vesicles
being torn or converted into mucus and absorbed, the globules
themselves formed by division are poured out into the
common mucous substratum. A t other times the primitive
globules, or more frequently the internal substance of the
second, the usual division being suspended, passes^ into very
minute granules, and the involucre of the globule itself converted
into mucous substance, gives birth in the same manner
to new globules. The frond in the beginning indeed
definite, nevertheless speedily becomes confiuent, and indefinitely
expanded. This genus, therefore, differs only from
Coccochloris in the division of the globules, which likewise
manifests an affinity to Pleurococcus.” — Meneghini.
The species included by me in the genus Hæmatococcus
admit of division into three subgenera. They embrace also
the genera Microcgstis and Pleurococcus of Meneghini, to distinguish
which genera I can find no satisfactory character.
First Suhgenus.— (y\oh\i\QS appendaged, that is, each terminates
or is imbedded in the extremity o f a distinct mucous
prolongation, the mass o f the plant being formed principally
o f these mucous prolongations.
The term Ouracoccus might be applied to the species of this
siibgeniis.
a. Mucous prolongation plain. Granules invested with a
single vesicle.
1. H æ m a to c o c c u s A llm a n i Hass.
P late L X X X . Fig. 3.
Char. Globules elliptical, large, blood-red, surrounded by a
single diaphanous margin.
C
Hab. Dropping Well, Knaresborough : P r o f G. J. Allman.
The globules of this species resemble in size and form
those of Coccochloris murorum, a species which might indeed
be referred to the genus Hæmatococcus, it differing from
Hæm. Allmani only in colour, and in so far as I can ascertain,
the absence of the mucous appendages. I f these ever be
present in Coccochloris murorum, then there can he no doubt
of the generic identity of the two plants.
Not being able to find tha t this plant has as yet been recorded,
I have great pleasure in naming it after my friend
Dr. Allman, from whom alone I have received the plant. The
specimens sent, although very fine, were not altogether free
from admixture, being mixed up with examples of Hæm.
Hookeriana. I t was on an examination of these specimens
th a t I first discovered the mucous appendages, of which I
immediately apprised Dr. Allman, who wrote to me as follows
: — “ Many thanks for your information. Your observation
on the structure of the Algæ I sent you is most
interesting. Though I distinctly enough detected a peculiar
organization in the gelatinous fiesh in which the capsules of
the Alga with red granules are imbedded, I saw nothing of
the singular arrangement you mention. Your observation is
certainly most interesting and original. I am longing to examine
the Alga, now that you have directed my attention to
the curious fact you mention.” The granules vary much in
size in this as well as in all other species of the genus Hæmatococcus.
The Hæm. sanguineus of Kützing may possibly be
referrihle to this, or perhaps more probably to th e /fe rn , crgp-
tophila, as it is described as having elliptical granules.
2. H æmatococcus murorum Hass.
Plate L X X X I . Fig. 4.
Char. Granules elliptical, æruginous green, free, surrounded '
bg a band, pellucid limbus.
Coccochlorum murorum Grev., Scot. Crypt. Fl. t. 6. No.
325. Microcgstis mellea? Menegh., loc. cit. t. xii. fig. 2.
Hab. Scotland ; Dr. Greville. Ireland : Mr. Moore.
T 2