belonging to a new Order of the Class Cirripedia. 318 
therefore be physically impossible for Serpule to develope them- 
selves on the under surface of such appendage. It is probable, 
then, that the basal plate of Lithotrya is nothing else but a broken 
valve of either Clavagella or of some small oyster that has been 
growing in the deserted abode most likely of Clavagella or 
perhaps of Lithodomus*. 
Chitia verruca, which is unprovided with a shelly base, cer- 
tainly sinks slightly mto the shells to which it adheres ; but this 
cannot be considered a burrowing Cirripede. -Alcippe lampas, 
the name by which I propose to designate our new species, is the 
only one of the class, which, according to our present knowledge, 
can be so considered. It is the only one, at least, that entirely 
conceals itself in chambers of its own making in hard calcareous 
bodies. 
I have not been able to examine into the method by which 
the excavations are effected; a fresh and numerous supply of 
specimens will be required for this purpose. I shall now only 
observe on this interesting part of the subject, that in this Cirri- 
pede we have a proof that an animal as highly organized as the 
Mollusca can bury itself in hard caleareous substances without 
the aid of shelly plates ; and that the walls of the burrow of this 
animal exhibit in a peculiar manner the structure of the shelly 
matrix. This however might result either from a solvent, or 
from the application of minute cutting bodies on a highly con- 
tractile, soft, and pliant surface. 
From the above general review of the characters and habits of 
this animal, we observe at once that it differs in so remarkable 
a manner from both the Campylosomata and Acamptosomata,— 
orders established by Leach for the accommodation of the two 
great divisions, the pedunculate and sessile Barnacles,—that it 
becomes necessary to form a new order for the reception of this 
curious Cirripede. This order I propose to characterize as fol- 
lows :— 
Order Cryprosomata. 
Animal naked, burying itself in some foreign substance, at- 
tached by muscular adhesion to the upper wall of the chamber, 
and communicating with the water by an orifice: arms or feet 
six, composed of three articulations, the last simple: branchiz 
setaceous, attached to the external surface of the upper lip. 
Genus ALCIPPE. 
Animal depressed and enlarged posteriorly ; anterior portion 
compressed, with the mantle sht longitudinally on the upper 
* Whilst this was passing through the press I have been assured by 
Mr. C. Darwin, and his opinion on this subject is of the greatest value, that 
the dorsal cup of Lithotrya is undoubtedly formed by the animal, and that it 
has the power of enlarging the cavities in which the larva takes up its abode. 
