10 
from (he inferior point of the junction oi these parts, anil 
directed obliquely upward to the edge; where they are 
opposite to similar lines on the smaller plate, which con- 
verge on a part of the superior margin a little distant 
from the point: from which latter portion similar lines 
pass obliquely upward and backward to the same space. 
The dorsal plate has a distinct smooth ridge or keel ; 
but possesses longitudinal lines passing from behind forward 
to the edge. Colour a leaden blue, the stalk short, almost 
sessile. 
Montagu ouco found this species, in an immature slate, 
attached to the Gorgotiia Flabellnm: a species of coral not 
yet beyond a doubt, as a native of the British be,as. Sonic 
specimens were presented to me by a young Lady, from the 
coast of Ireland ; aud on the following day I was so fortu- 
nate as to find a collection of them, attached in clumps on 
both sides of a piece of the bark of a tree. Comparing these 
with Montagu’s description and figure, I find the terminal 
side plate less sharp, and the characteristic raised lines more 
numerous ; for in Montagu’s specimens there were no more 
than 15, which he terms strong ribs; while in the larger 
individuals from which my description was drawn, there 
were 28 in one, and 29 in another. On the lesser side plate 
I counted 17, instead of seven or eight as noticed by Montagu. 
All of them were of an equal marking, so as to give the 
specimens an elegant appearance : the plates closely joined, 
without an appearance of membrane; and the lines on both 
plates continuous, instead of forming an angle, as in Mon- 
tagu’s figure. The Irish specimens in this respect approach 
more nearly to the engraving ; their breadth being greater 
than the Cornish, in comparison with their length : the plates 
also of a firmer texture, with a few undulations crossing the 
raised lines ; those on the anterior plates also standing at an 
angle with those behind. But these again differ from Mon- 
tagu’s specimens in having 38 lines on the hinder plate, and 
20 on the anterior, with none on the dorsal plate. 1 he 
overlapping of the right plate over the left, is common to the 
whole of these specimens and Montagu’s figure. Shortly 
after the discovery of these specimens, I obtained a piece oj 
cork, such as is employed by fishermen tor their nets ; and 
on one side of it were found several small specimens ot this 
Barnacle, scattered singly over its surface. Including the 
footstalk which indeed is too short to enter into the measure- 
ment, their length did not exceed the tenth of an inch; and 
their structure was more rough and unsightly, the raisei 
lines less numerous and regular, than in my former an 
larger specimens. About the same time also, Mr. Jackson, 
