i,
a larger form of the plant ; and an illustration of it, may be seen at
figure 7. in the ninth plate of Dillenius’ “ Historia Muscorum.” The
frond, according to Agardh, is nearly an inch in diameter. Like the
following species, however, the gradation from one form to another is
quite insensible. 1 have specimens, from the Isle of Bute, between
two and three feet in length, and, in the upper part, above three
inches in diameter. But the most remarkable individual that has come
under my notice, is one communicated by M. Chauvin ; it ia about a
foot in length, and from three to four inches in width, lobed, crisped,
and curled in the most extraordinary manner all along the margin, or
rather over the whole surface.
When floating so as to cover the surface of the water in ditches, the
frond often becomes inflated with air-bubbles, as if in a state of fermentation.
2. E n t e r o m o r p h a c om p re s s a . Tab. X V III.
Frond tubular, compressed, regularly reticulated, filiform, branched,
the branches simple, attenuated at their base.
Solenia compressa, A g . S y s t . A lg . p . 186. S p i e n g . S p . P I . v . 4. p . 367- B o ry , in D u -
p e r r e y V o y . (B o t.) p . 201.
Fiatularia compressa, G r e v . F I . E d in . p . 300.
Viva compressa, L in n . F L S u e c . p . 433. L ig h t f . F I . S c o t. p . 96i). Ag . S p . A lg . v . L
p . 420. S m i th ; E n g . B o t. t . 2739.
Ilea compressa, G a ill. D i e t . S c . N a t . v . 53. p . 373.
Conferva compressa, R o th . C a t . B o t. v . 1. p . 161.
V a b . /3 prolifera, f r o n d s om ew h a t in f la te d , th r o w in g o u t c a p illa ry b r a n c h e s o n a l l sid e s.
Solenia compressa, v a r . prolifera, A g . S y s t. A lg . p . 186.
Viva prolifera, F I . D a n . t . 7 6 3 . f . 1.
Scytosiphon compressus, v a r . crispatus, L y n g b . H y d r o p h . D a n . p . 64. t . 15.
H a b . On rocks and stones and piles in the sea. Annual. Spring
and summer. Extremely common.
Root a minute disk. Fronds six to twelve inches in length, and
from the fineness of a hair to several lines in diameter, aggregated, filiform,
branched, tubular, more or less compressed, frequently constricted
here and there, and mostly increasing insensibly in diameter from
the base to the middle, or even to the summit ; branches usually arising
near the base, simple, elongated, and much attenuated towards their
insertion, the apex obtuse. Substance tender, thin, membranaceous.
Colour a fine herbaceous green, paler towards the base, changing to
white in decay. In drying it retains its colour, and adheres imperfectly
to paper.
In variety g, a number of capillary ramuli arise from the whole surface
of the frond in a proliferous manner. Agardh suggests that it may
possibly prove a variety of E. intestinalis. A specimen presented to
me by M. Chauvin, I should refer to the species before u s; at the
same time, a highly proliferous variety, of what seems otherwise to be E.
intestinalis, is represented in the Dictionnaire des Sciences Naturelles.
Another variety of E. compressa is entirely capillary, almost like a
Conferva; this is the Conferva crinita of Roth (Cat. Bot. v. 1. t. 1.
f. 3.), and the Ulva capillaris of Lamouroux. I am not aware that it
has been found in this country.
The structure of this plant is described by Agardh as regularly reticulated,
and the reticulations disposed in parallel lines. The latter
part of the character I have never been able to perceive distinctly, and
have represented the result of my own microscopical investigation.
The shores of almost every country from the Arctic to the Antarctic
Ocean produce this species. In the Sandwich Islands it forms an ai'-
ticle of food.
3 . E n t e r o m o r p h a c l a t h r a t a .
Frond tubular, filiform, much branched, irregularly reticulated,
branches capillary, attenuated.
Solenia clathrata, Ag. S y s t. A lg . p . 186. S p r e n g . S p . P I . v . 4. p . 368.
Scytosiphon clathratus, L y n g b . H y d r o p h . D a n . p . 6 6 . 1 . 16.
Scytosiphon paradoxus, F I . D a n . 1. 1595. f. 2.
Viva clathrata, Ag. S y n . p . 46.
Ilea clathrata, G a ill. D ie t . S c . N a t . v . 53. p . 373.
Conferva clathrata, R o th . C a t. B o t. v . 3. p . 175.
Conferva paradoxa, D illw . B r i t . C o n f . (S y n .) p . 70. t . F . S m . E n g . B o t. t . 2328-
V a b . p, erecta, b r a n c h e s v e r y lo n g , s om ew h a t e r e c t , n e a r ly s im p le o r s e t w i th sm a ll
s c a t t e r e d r am u l i .
Scytosiphon erectus, L y n g b . H y d r o p h . D a n . p . 6 5 . 1 . 15.
Fistularia erecta, G r e v . F I . E d in . p . 300.
Solenia clathrata, v a r . confervoidea, A g . S y s t. A lg . p . 187*
V a b . y uncinata, f r o n d m u c h b r a n c h e d , t h e r am u l i s h o r t , c row d e d a n d s p r e a d in g .
Solenia clathrata, v a r . uncinata, A g . S y s t . A lg . p . 187.
Viva uncinata, M o h r . C a t. A lg . a c c o rd in g to A g a rd h .
Viva ramulosa, S m . E n g . B o t. t . 2137*
Viva confervoides, L am o u r . E s s a i, p . 65. a c c o rd in g t o A g a rd h .
H a b . In the sea. Said also to grow in fresh water. Annual.
Spring and summer. Probably common. In the sea near Bangor,
Mr Templeton. Brighton, Mr Borrer- Var. g, in the Frith of Forth
not unfrequent, aud on the shores of the Isle of Bute. Var. y, in Bantry
Bay, Miss Hutchins.