OF CORNWALL. 237 
N°. l v 1 1 1 . Fucus longo angujlo crajjoque folio , lea-thongs 1 . At 
the root or clafpers of this plant there is a concave capfulous part, 
the ufe of which has not hitherto been explained. Mr. Ray m calls 
it Rotula latiufcula caulem props radicem velut axe?n ambiens. Hap- 
pening to land on the Geer (a rock half a mile fouth of Penzance 
pier, covered with the tide eight hours in twelve) in fearch of Co- 
rallines with Dr. J. Albert Schloffer, F. R. S. a very curious and 
learned foreigner, in the year 1755, it was our fortune to fee this 
fucus in its feveral ftages of growth, but not one without this cir- 
cular cavity. In fome of them the fea-thongs were in their moft 
infant Fate, the gemmae or fir ft buds appearing no other than 
papillae , in the center of the cup-like cavity, which in this ftate 
was very concave ; in others the thongs were from an inch, two, 
three, and four, to four feet long, the capfuloe becoming lefs con- 
cave in proportion to the ftze and age of the plant ; by which 
different ftages of growth, it appears, that this cup is the upper 
part, or firft fheath of this plant, deftgned by nature to fhelter and 
protecft, by its cup-like cavity, the firft tender buds of the fucus , 
till the fixings within this fheath have gained a little ftrength and 
footing, fufticient to wade further into the fea, and by its flexibility 
able to elude the violence of the water : I will only obferve farther, 
that though the fea-thong begins with a little bud no bigger than 
that of a line in diameter, yet it extends itfelf oftentimes to a great 
length : On the fhore of Mount’s Bay, in the month of July 1757, 
I meafured fome, and found them above twenty feet in length ; they 
have alfo been meafured in Falmouth Harbour, and found twenty- 
one feet in length. On the fame fhores with this Alga , are often- Sponges, 
times found fponges, ufually affixed to the rocks, fhells, or fands ; 
fome of which are leafy, having their parts {hooting into the fhapes 
ol curled leaves (as are thofe found on the fhore near Loo) ; fome 
are branchy, as the Spongia ramofa fome are folid oblong balls, 
which inclofe a fifhy embryo, Spongia denftffma fpijfa valiaa cine- 
rea " ; fome full of large round holes at the top of its tubercles, of 
a purplifh colour when taken out of the water, but foon fading to 
that of common fponge ; this fort has a cavity ahb underneath, as 
if fome living creatures had neftled there, and ufed thefe holes as 
paflages into the central cavity * ; moft likely it is a kind of crab 
which lodges its foetus in thefe fpongy receptacles for their fecurity, 
as Rondeletius intimates 
Many other forts there are doubtlefs of the Alga, and many other 
fubmarines on the fea-fhores of Cornwall ; but it is now time to ob- 
ferve, that of thefe herbaceous lea-plants there are feveral ufes. In 
1 Ray, 2 d edit, page 5. * Some think the whole fponge to be the work 
m Ibidem. of infefts, but however that be, the animals above- 
n Rondelet, page 1 34. mentioned are adventitious. j “ Ibid. 
P p p the 
