belonging to a new Order of the Class Cirripedia. 313 



therefore be physically impossible for Serpulce 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*. 



Clitia verruca, which is unprovided with a shelly base, cer- 

 tainly sinks slightly into 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 calcareous 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 Cryptosomata. 



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 : branchiae 

 setaceous, attached to the external surface of the upper lip. 



Genus Alcippe. 

 Animal depressed and enlarged posteriorly ; anterior portion 

 compressed, with the mantle slit 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. 



