belonging to a new Order of the Class Cirripedia. 309 



bifid, and exhibit for some distance upwards the appearance qf 

 two channels (fig. 8). There can be little doubt that these or- 

 gans are for branchial purposes. 



The chamber in which the animal is lodged is partially lined 

 with calcareous matter secreted by the tenant ; this lining is very 

 thin, and principally confined to the side walls of that part in 

 which the anterior portion of the animal is lodged : here the 

 lining gradually thickens as it approaches the margins of the slit, 

 and passes a little beyond them, particularly towards its poste- 

 rior termination. On looking down upon the slit this shelly 

 lining (fig. 2 c) is seen distinctly projecting inwards from the 

 margins, and exhibiting two or three longitudinal ridges mark- 

 ing periods of growth, narrowing the opening backwards as the 

 increase of the animal requires the advancement of the aperture 

 in front. Shelly granules, d, may also occasionally be seen filling 

 up the curved posterior extremity of the slit. 



Notwithstanding the abundance of this animal I have not yet 

 been able to investigate the internal anatomy, many specimens 

 having necessarily been destroyed in making the external exami- 

 nations, and others suff'ered in attempts to remove them from 

 their abode. This important part of the description must there- 

 fore for the present be left almost untouched. 



The cloak below is free for a considerable way backwards ; 

 above, immediately behind the slit, it is united in front with the 

 true body of the animal, and behind, where the broad disc-like 

 expansion is covered with the horny plate, it blends with a 

 thickish layer of parenchymatous matter. The stomach is long 

 and narrow, and passing downwards and backwards from the 

 mouth bends rather suddenly forwards, and gradually tapering 

 is continued into the cylindrical, fleshy pedicle which supports 

 the arms, near to which it probably terminates. No caudal pro- 

 longation of this part was observed similar to that which is com- 

 mon to all the other Cirripedes ; the generative organs are there- 

 fore probably modified in this animal. 



Adhering to the parenchymatous matter beneath the horny 

 plate the eggs are found spread out into a leaf-like expansion 

 co-extensive with this part of the animal ; but whether or not 

 this is really the ovarium could not be determined. It may be 

 that the eggs have reached this position in some such way as 

 they are supposed by certain writers to arrive in the pedicle of 

 the pedunculate Barnacles. However, in this animal it is certain 

 that the ova are never arranged in laminoe at the base of the arms 

 as in the other Cirripedes, but that they are hatched in the posi- 

 tion in which they have just been described. Of this I have had 

 ocular proof. 



In the early stages of development the eggs (PL IX. figs. 5 



