REPORT ON THE COPEPODA. 39 



antepenultimate each with two long apical setae. In the male the joints are constricted 

 at the points of articulation. I have altogether failed to find the beautifully plumose 

 hairs figured by Lubbock and Dana as belonging to the apex of the anterior antennae. 

 Inner branch of the posterior antenna eight-jointed, the two basal joints large, last six 

 joints very small and nearly equal. The inner branches of all the swimming feet (fig. 8) 

 are three-jointed ; the marginal spines of the outer branches small ; terminal spines very 

 slender, scarcely distinguishable from the marginal setae, but bordered externally with a 

 very delicate faintly pectinated lamina. The feet of the fifth pair in the male (PI. II. fig. 10) 

 are three-jointed, the left limb longer than the right, each bearing a single small apical 

 hair. In the female the posterior foot-jaws (fig. 9) have the three proximal tufts of setae 

 only plumose. 



Habitat. — Between Api and Cape York ; between Arrou and Banda ; off the south of 

 Papua ; off Sibrabo Island, Philippines, and in various other gatherings from amongst the 

 Philippine Islands; in lat. 46° 46' S., long. 45° 31' E. (Station 146); lat. 47° 25' S., 

 long. 130° 32' E. (Station 159); off Port Jackson, at night; between Sydney and 

 Wellington ; off Kandavu, Fiji ; in the tropical Atlantic off the west coast of Africa, 

 between lat. 3° 10' N., long. 14° 51° W. (Station 348) ; and lat. 7° 33' N., long. 15* 16' 

 W. (Station 350) ; and in lat. 45° 31' S., long. 78° 9' W. (Station 303). 



It will be seen from the foregoing list, that almost all the Challenger gatherings in 

 which this species was noticed, are from the Malayan and Australasian Seas, the excep- 

 tions being those from the west coasts of Patagonia and Africa. Professor Dana's 

 specimens, however, were from the Pacific (Kingsmill Islands) and China Seas ; Sir John 

 Lubbock's from the Bay of Biscay, and Dr. Claus's (which as I think are in all probability 

 identical with the present species) from the Mediterranean. There can scarcely be a 

 better instance of the very wide distribution of a species, which is nowhere perhaps very 

 abundant when compared with such as Calanus Jinmarchicus, Anomalocera patersonii or 

 Undina vulgaris. Further research may perhaps show differences sufficient to require 

 specific recognition, but if so, the relationship between the various species may be 

 expected to be very close indeed, showing not greater divergence than might be the 

 result of prolonged exposure to somewhat different external conditions. The anterior 

 antennae (PL VI. fig. 1) are inaccurately drawn, showing too large a number of joints. 

 When the figure was drawn I had not seen a specimen with perfect antennae, and the 

 drawing was made up from observations of several animals : the number of joints ought 

 to be twenty-three. 



2. Eucalanus setiger, n. sp. (PI. III. figs. 8-15). 



Length, l-7th of an inch (3"5 mm.). Forehead broadly rounded, with little or no 

 constriction behind, rostrum with a long, stout base and slender bifid apex ; head not at 



