belonging to a new Order of the Class Cirripedia. 311 
are three pairs of natatory legs placed well forwards and indi- 
stinetly articulated ; the anterior pair are simple and furnished 
with a few long sete at their extremities ; the other two pairs are 
bifid, the anterior portion being much the stouter, and marked 
with several indistinct close-set articulations towards the extre- 
mity ; each articulation bearing on its posterior margin a long 
seta: the posterior branch of the limb is also furnished with sete 
at its extremity. On each side of the head there is a stout pro- 
cess a little arched backwards with the pot obtuse; these I am 
inclined to look upon as antenne, for they appear to arise from 
the head beneath the shield, though this could not be determined 
with certainty. It is possible enough that they are lateral pro- 
longations of the shield, similar to the “anterior horns ” of the 
larva of the pedunculate Cirripedes. Whether so or not, the 
larva of this new animal may at once be distinguished from that 
of this division of the Barnacles by the absence of the long spine 
projecting from the posterior margin of the shield. In other 
respects it evidently shows a strong general resemblance to the 
‘larva of these animals. 
The larva, then, as well as the characters of the animal itself, 
proves it to be a true Cirripede, while, in the former, we see a 
confirmation of the relationship shown by Thompson to exist 
between these creatures and the Crustaceans. Indeed this ani- 
mal in several particulars exhibits a very close approximation to 
them. The shape of the arms or palps by the sides of the mouth 
resembles not a little the mandibles of the Nymphons or the ante- 
rior feet of some of the higher forms ; and the horny shield over- 
lying the expanded portion of the animal gives somewhat the 
idea of a rudimentary carapace : the rostrated upper lip, too, and 
setaceous branchiz have likewise a very crustacean appearance. 
In these particulars our new animal differs from the typical 
Cirripedes ; but not more than in general form, which is very 
unlike that of either of the two great divisions of the class. The 
prehensile arms or feet, too, are highly characteristic in this, 
having, in fact, more the appearance of true feet than the cirri of 
the other Cirripedes ; there are only six, or three pairs, while in 
all the other Barnacles there are double that number, or six pairs. 
In our animal the last or terminal joint is shortest and is simple, 
having few and comparatively short setze: the arms or feet indeed 
appear to be merely prehensile organs laying hold of prey by the 
aid of the cushion-like swellings before described as attached to 
their inner margins. 
The cirrigerous feet of the other Cirripedes are also undoubt- 
edly prehensile, but im a very different manner. In these each 
terminates in a pair of slender, muclt-elongated and curled cirri 
composed of numerous, minute articulations, furnished with a 
