i I
P l a t e CCLXI.
ELACHISTEA STELLULATA, Griff.
G e n . Ch a k. Frond parasitical, consisting of a dense tuft of free, simple,
articulated, olivaceous fllaments, rising from a common tubercular
base, composed of vertical, branching fibres, closely combined into a
cartilaginous mass. Fructification, pear-shaped spores attached to the
bases of the filaments concealed in the tubercle, and frequently accompanied
by paranemata. E lachistea {Fries), — from Aaxio-ra,
the lea s t; from the small size of these plants.
E lachistea steltulata ; tufts very minute, stellate ; tubercle composed of
large cells ; filaments short, tapering to the base, linear club-shaped,
obtuse ; articulations about twice as long as broad, uniform ; paranemata
with short articulations.
E l a c h i s t e a s te l lu l a ta . Griff. MSS. Aresch. Pug. in Linn. v o l. x v ii. p . 2 6 1 .
t a b . 9 . f. 4 . H a n . Man. e d . 2 . p . 5 1 .
M y e i o n e m a s teU u la tum , / . Ag. et Gen. Sp. Alg. v o l. i. p . 4 9 .
C o n f e r v a s te l lu l a ta , Harv. Man. e d . 1 . p . 1 3 2 .
Ha b . Parasitical on Dietyota dichotoma. Annual. Summer. Torquay,
G e o g e . D i s t r . Not observed out of England.
D e s o r . Tufits exceedingly minute, scarcely half a line in diameter, appearing
Hke dark brown specks, dotting over the sm-face of the Diotyota, and under
the microscope resembhng miniature echini. Tubercle well developed, composed
of dichotomous strings of large, colourless cells. From the terminal
cell of each string the filaments and paranemata arise. Filaments a quarter
of a Hue in length, Hnear-clavate, gradually tapering from the obtuse apex
to the base the articulations of nearly uniform size, aU being from once and
a half to twice as long as broad, constricted at the joints. Each articulation
contains a bag of rather dark coloured endochrome. Paranemata very
numerous, springing with the filaments, and about one-third as long, ivith
very short articulations, club-shaped. Spores unknown to me. They are
figured by Dr. Areschoug as obovate-oblong.
This minute and microscopically beautiful little plant was discovered
some years ago by Mrs. Griffiths on the old fronds of
Dietyota dichotoma, and first described in the first edition of the
Manual of British Algse. I have not seen any other specimens
than those originally collected by Mrs. Griffiths, who met with
the parasite infesting several specimens of the Dietyota ■, nor am
1 aware that any other observer has noticed it in Britain, or that