history of this plant, from which it appears that it was known to the 
naturalists of France under the name of Dumontia Calvadosit, 
long before it was noticed on the shores of the British Islands. 
I was not aware of this fact, when, in 1832, I described, under 
the name of Mesogloia purpurea, specimens which were collected 
by Mrs. Griffiths, in the autumn of 1828, at Sidmouth. The 
resemblance to Dumontia is only an outward one; the structure 
is completely that of the Gloioc/adiee, and not very unlike that of 
Mesogloia vermicularis, though, according to our present syste- 
matic arrangement, these plants belong to different genera, and 
even to different families. In altering the genus of this plant, 
M. Chauvin had the option of restoring the specific name under 
which it was first described, but he has not thought fit to do so. 
The structure of this species differs considerably from that of 
LV. multifidum (already figured at Plate XXXVI.), and probably 
may justify the future formation of a genus, when the fructifica- 
tion of both plants shall be more perfectly known. In our J. 
purpureum, the axis is composed of much more laxly set filaments; 
while those of the periphery are less branched, shorter, and 
composed of very large, pear-shaped cells. Seen under a lens 
of low power, the branches appear like tubes of glass, densely 
covered with brilliant purple studs. 
Nemaleon purpureum is a rare species on the British shores, 
though occasionally thrown up in considerable quantities. This 
occurred at Sidmouth when Mrs. Griffiths first found the plant, 
but for several succeeding years it did not make its appearance. 
The specimens then collected were also of a much brighter 
colour, as well as larger and more luxuriant, than any which 
have been sent to me from other stations, or than I have myself 
gathered. I once found it growmg on sandy ground near low- 
water mark; but it is more usually seen among rejectamenta 
after a gale. 
Fig. 1. NEMALEON? PURPUREUM:—of the natural size. 2. Portion of a 
branch :—moderately magnified. 3. Some of the filaments, composing the 
same :—highly magnified. 
