84 THE VOYAGE OF H.M.S. CHALLENGER. 



slightly dilated in the middle ; the joints on each side of the hinge bear delicately 

 serrated marginal plates, and at the base of each plate there is a small spine. The 

 terminal spines of the swimming feet are very slender, scarcely stouter than the 

 marginal setae. The outer branch of the fifth foot in the female (fig. 11) has its inner 

 apical angle produced into a stout spine, which does not reach more than half the 

 length of the third joint. In the male the fifth foot of the right side (fig. 12) is 

 prehensile, the middle joint of the outer branch forming a robust, blunt, claw-like 

 process, while the last joint bears at the apex a long, slender, doubly-curved, or S-shaped 

 claw; the left foot has the last joint of its outer branch (fig. 13) distorted at the extremity, 

 where it bears three short spine-like setae. The abdomen in the male is elongated, but 

 in the female short and stout; the caudal segments are flattened, slightly divergent, and 

 scarcely twice as long as broad ; seta? six, subequal, stout, shorter than the abdomen ; in 

 the female (fig. 14) the place of the second seta — counting from the outside — is usually 

 occupied by a stout club-shaped appendage. 



Habitat. — Off Cape Howe, Australia; off the Philippine Islands; Pacific, east of Japan, 

 lat. 30° 22' N., long. 154° 56' W. (Station 256) ; South Pacific, October 18, 1875 (near 

 Station 287) ; Atlantic, lat. 40° 3' S., long. 132° 58' W. (Station 288); lat. 42° 43' S., 

 long. 82° 11' W. (Station 302) ; lat. 37° 3' S., long. 44° 17' W. (Station 326) ; lat, 37° 

 31' S., long. 36° 7' W. (Station 329); lat. 9° 43' S., long. 13° 51' W. (Station 342); 

 North Atlantic, lat. 26° 21' N., long. 36° 6' W. In many of these places the species 

 occurred in considerable abundance, showing a very extensive range of distribution, 

 from the Mediterranean on the north to the coast of Patagonia southward, and to 

 Japan, the Philippine Islands, and Australia in the east. 



Dr. Claus describes his IcMhyophoi-ba violacea as being violet-coloured with red 

 spots. Such a description would perhaps not inaptly apply to the Challenger specimens 

 when fresh, and I am the more inclined to suppose so, as the spirit specimens may be 

 very readily separated from the bulk of the gatherings in which they occur by the 

 presence of a cloudy purphsh-brown patch on the body of each. This very probably 

 represents the more diffused colouring of the living animal after being acted on by 

 preservative fluid. The other points of Dr. Claus' description accord perfectly with our 

 specimens, except as to the left fifth foot of the male, in which I find three terminal 

 setae instead of only two. The peculiar setose armature of the caudal segments in the 

 female is not noticed by Dr. Claus. 



Calanopia, Dana. 

 Calanopia, Dana, in part, 1852. 

 Anterior antennas eighteen-jointed, that of the right side in the male geniculated, 

 provided with two denticulated plates, and somewhat angulated at the flexures. Mouth- 



