REPORT ON THE CIRR1PEDIA. 



11 



between the carina! margin of the two carinal latent. Lower margin considerably 

 convex ; upper margin slightly concave. 



Length of capitulum, about 4<> mm. 



Peduncle long (31 mm.), .stout, growing wider towards the 

 upper end, though even here by no means attaining the width 

 of the capitulum. Whereas the capitulum is, especially in Hi'' 

 upper part, much flattened, the peduncle is circular in section. 

 The peduncle is also covered by membrane ; the transverselj 

 elongated scales therefore not very distinct, a little more 

 so in the lower part of the peduncle. 



The accompanying woodcut (fig. 3) shows tin; way in 

 which the only specimen of this species was attached to a 

 manganese nodule. These nodules, Mr. Murray informs me, 

 are formed by concretionary depositions around sharks' teeth, 

 pumice, and other substances at the bottom. 



I have not studied the structure of the animal contained 

 within the valves. I found four complemental males attached 

 between the mantle and the scutum, at a short distance from 

 the apex of the valve and close to its occludent margin. 

 Three specimens were on the left and one on the right 

 side. They have the same shape as those of Scalpellum 

 regium, but they are considerably larger, having a length of 

 27 mm. Small prehensile antennas indicate the anterior 

 extremity of the body, the opening of the genital duct being 

 at the other extremity. The great size of the males enabled 



me to make preparations of their anatomy ; with the aid of which the figures on 

 PI. X. are drawn. The wall of the body is distinctly seen under that which represents 

 the mantle ; muscles are attached to the former, and the latter is covered by very minute 

 bristles. 



This species was taken at Station 299, December 14, 1875; lat. 33° 31' S., long. 

 74° 43' W. ; depth, 2160 fathoms; bottom temperature, 1° - 1 C. ; bottom, grey 

 mud. 



Fig. 3.— Scalpellum darwinii, at- 

 tached to a nodule of manganese. 



(b.) Species without a Rostrum. 



Scalpellum distinctum, n. sp. (PI. VI. figs. 10, 11). 



Valves thirteen, not covered by membrane, separated from each other by distinct 

 chitinous interspaces. Carina with the umbo at the apex, simply bowed, with a flat roof 



