The Hifory of ANIMALS. 
172 
Balanus tenuior valvis elevatis , ore angufliore. 
The narrow-mouthef fender Balanus , with elevated valves . 
This is a very Angular fpecies; it is three quarters of an inch high, and not more 
than a third of an inch in diameter in the larged; part, which is a little lower than the 
middle: the bale is fomewhat fmaller than this part, and the fummit is much more 
fo; the verge of the fhell is contracted, and the aperture or mouth fmall : it is formed 
of eight valves, connected by an intermediated thinner fubftance: the valves form fo 
many ribs, as it were, approaching very near one another at their fides; but, their form 
rendering the intermediate fubftance vifible, it is diftinCtly feen, though not broader 
than in the former fpecies, in which it is fcarce vifible at all: the ribs are of a round¬ 
ed form, confiderably elevated in the middle, and are of a brownifh-grey colour 5 the 
intermediate matter is of a pale grey, without any admixture of the brown. 
This fpecies is extreamly common in the Eaft Indies, and on the coaft of Africa: 
it has alfo been brought from fome of the European fhores. 
Balanus tenuior valvis flriatis purpurafcens , ore angufo . 
The purple , narrow- mouth edy fender Balanus, with ftriated valves . 
This is three quarters of an inch high, and little more than a third of an inch in 
diameter: it is larged at the very bafe, and thence grows gradually fmaller all the way 
to the top; fo that, where there are large clufters of it, there are found tolerably 
large fpaces between the extremities, which become gradually fmaller all the way to¬ 
ward the bafes of the fhells : each fhell is compofed of only fix valves or ribs, which 
are broadeft at the bafes, and there touch one another ; but, growing narrower all the 
way, they are connected by a thin but fufficiently firm fheliy matter, which toward 
the top makes by much the greater part of the fubftance: the valves or ribs, as they 
are called by many, are flatted, and deeply, but not very regularly, ftriated, in a lon¬ 
gitudinal direction: the intermediate fubftance is undulated tranfverfely; the verge is 
fomewhat contracted toward the center, fo as to form a narrow mouth : the whole 
fhell is of an elegant purple colour, but the ribs, are deeper, and have more of the 
blue, the intermediate matter is paler, and has more of the red. 
We have it from the American fhores, but it is not common. 
k 
Balanus tenuior friatus grifeo-alhefcens , ore angufo . 
The greyijh-white 3 flriated , fender Balanus , with a narrow ?nouth, 
» * . . 
This is a fmall fpecies; it rarely exceeds a third of an inch in length, and is hardly 
equal to a third of it’s length in diameter: it is broadeft at the bafe, and thence, be¬ 
comes gradually fmaller to the top, where it is contracted inward a little, fo as to form 
but a narrow mouth : the colour is a greyifh-white, and the whole fhell fo thin, that 
it is eafily crufhed and broken: it is compofed of only fix valves, which are largeft 
at the bafe, and thence become gradually fmaller to the top; they are ftriated in a 
longitudinal direction, and the ftrias are deepeft and moft diftinCt toward the top; 
in the lower part they are fcarce vifible : the intermediate matter is alfo irregularly un¬ 
dulated, but it is in a direction contrary to that of the valves. 
This fpecies is frequent about our own fhores, on ftones, and on the fhells of other 
fhell-fifh. 
) 
Balanus tenuior ore angufo , valvis angufijfmis rotundatis flavis . 
The fender Balanus 3 with a narrow-mouthy and with the valves rounded 
and yellow . 
This is about half an inch in height, and is barely a quarter of an inch in diameter 
in the largeft part, which is toward the middle; from this part to the bafe it becomes 
gradually a little fmaller, and toward the fummit more fo: it’s colour is a dufky 
brownifh-yellow on the ribs or valves, and a paler yellow, with lefs of the brown in 
it between them : the valves are twelve in number; they are very narrow, of a round¬ 
ed figure, and ftand at very fmall diftances. 
It 
