410 BALANIDvE. 



transversely, and does not differ essentially from that of most 

 other Balanidae. The labrum is notched and not in the 

 least bullate, though in C. diadema there is a slight promi- 

 nence outside close beneath the notch. The palpi are of 

 large size, with their bristly apices touching each other. The 

 mandibles are very strong, with from four to five main teeth, 

 which are remarkable by presenting only rudiments of 

 being laterally double ; but between the second and third, 

 and between the third and fourth main teeth, there is a small 

 intermediate tooth, — these I have not met with in any sessile 

 cirripede hitherto described. The maxillae are small, with 

 the two upper spines remarkably strong. The outer max- 

 illae are on their inner faces bilobed. Between these organs 

 there is a minute projection, or mentum, flattened in the 

 longitudinal axis of the body ; I have not noticed this in 

 any previous Cirripede. 



The Cirri are short and extremelv much flattened : the 

 three anterior pairs have their rami unequal in length by 

 two or three segments ; the posterior edges of their pedicels 

 are fringed by tufts of extremely fine hairs. The pedicel 

 of the first cirrus is very broad ; its rami are short, with 

 the segments verv broad. The rami of the second and 

 third cirri are short, with the segments protuberant in 

 front and thickly clothed with spines ; the terminal seg- 

 ments have some short, thick, claw-like spines. The three 

 posterior pairs have protuberant segments, each supporting 

 three or four pairs of short, strong, main spines, with a 

 small intermediate tuft : the dorsal tuft is small. 



The prosoma is of large size. The stomach is large, 

 without caeca, but with some internal longitudinal plaits 

 fin C. balcenaris at least), showing a tendency to the 

 formation of caeca. In the stomach of C. balcenaris I found 

 a considerable quantity of a conferva, too much, 1 think, to 

 have got in accidentally. 



Generative system. — The vesiculae seminales are large ; 

 and at their broad blunt ends, in C. balcenaris, four separate 

 vasa deferentia enter, of which fact I have seen no other 

 instance. The ovarian tubes do not extend up the sides of 

 the sack, but lie at the bottom, over the basal membrane ; 

 in C. balcenaris they send six short ray-like prolongations 



