COPEPODA. 
Q O 
O'J 
XANTHOCALANUS (Giesbrecht). 
* 
There are only two examples of this genus in the ‘ Discovery ’ collection. Since 
the publication of Giesbrecht and Schmeil’s “ Copepoda ” (in “ Tierreich ”) the genus has 
received many additional species. To the originally described species, viz., X. agilis 
and X. minor (Giesbrecht), are now added X. borealis (Sars), X. propinquus (Sars), 
X. muticus (Sars), X cristatus (Wolfenden), X. subcristatus (Wolfenden), X. simplex 
(Wolfenden), X. magnus (Wolfenden), X. calaminus (Wolfenden), X. atlanticus 
(Wolfenden), X. greeni (Farran), X. pinguis (Farran), and X. obtusus (Farran) ; and, 
as they are described in scattered publications, it may be well to recapitulate the 
characters here. 
1. X. AGILIS. 
X. agilis, Giesbrecht, Fauna u. FI. Neap. XIX. (1892), p. 286. 
Size 2'4 ; furcal segments broader than long, abdominal segments very hirsute ; 
anterior antennae reaching end of furca; fifth feet three segments, beset with spines 
and teeth, and with three apical teeth. 
In the 6 only one (the left) foot five-jointed. (Mediterranean.) 
2. X. SUBAGILIS. 
X. subagilis, Wolfenden, Jour. Mar. Biol. Assoc., VII. (1904), p. 118. 
Size 2'6 mm., resembling X. agilis , but abdominal segments not hirsute. 
Fifth feet with three segments, the basal with strong teeth, the middle with only 
hairs, the distal spinulose and with three long apical spines. 
6 with a pair of fifth feet nearly equal, the right of four, the left of five 
segments. (Mull of Galloway.) 
3. X. BOREALIS. 
i 
X. borealis, Sars, Crustacea of Norway, Yol. IV., p. 46. 
Size 3'50 mm. ; furcal segments as broad as long, anterior antenna? reach end of 
genital segment; fifth feet of three segments, proximal two, with teeth on inner 
margin ; last with two apical and two lateral spines. 
$ with a pair of fifth feet left of five segments, right very short and of only three 
segments. (Polar Seas. Norway.) 
4. X. PROPINQUUS. 
X. yropinqims, Sars, loc. cit. 
Size 1 '75 mm. ; furcal rami longer than broad; anterior antennae slender and 
reaching only to second abdominal segment, posterior antennae with Re much longer 
