COPEPODA. 
35 
10. X. ATLANTICUS. 
X. atlanticus, Wolfenden, Jour. Mar. Biol. Assoc., April, 1904. 
Size 2'5 mm. ; anterior antennae much shorter than thorax and very thick basally, 
abdominal segments prickly and hirsute, feet very spinulose ; fifth of three segments, 
distal the largest, with four large articulating spines, two apical, two lateral ; all 
segments very spinulose; furcal rami as broad as long, and Re of posterior antennae 
much longer than Ri. (West of Ireland.) 
11. X. OBTCJSUS. 
X. olttusus, Farran, Ann. Rep. Fish., Ireland, 1902-03, pt. ii., App. II. (1905), p. 40. 
Size 2 - 4 mm. Furcal rami little longer than broad, anterior antennae reach genital 
segment, feet very spinulose. Fifth feet, three segmented, spinulose, and with two 
terminal and two lateral spines on last segment; second joint longest, and spinulose on 
both margins. (Atlantic. Ireland.) 
12. X. PINGGIS. 
X. pinguis, Farran, Ann. Rep. Fish., Ireland, 1902-03, pt. ii., App. II. (1905), p. 40. 
Size 4‘5 mm. Head imperfectly separated from thorax; lateral processes of 
last segment blunt; furcal segments slightly longer than broad ; anterior antennae 
short, not as long as thorax ; rami of posterior antennae short and broad ; feet spinulose. 
Fifth feet of three segments, and two lateral and two apical end spines ; surface of 
third and margins of first (inner) and second (outer) spinulose. (Atlantic. Ireland.) 
13. X. GREENI. X. MUTICUS. 
X. greeni, Farran, Ann. Rep. Fish., Ireland, 1902-03, pt. ii., App. II. (1905), p. 40. X. muticus, Sars, 
Bull. Mus. Monaco. 
Size 5‘30-6 mm. ; last two segments of thorax united, last segment with obtusely 
triangular margins ; furcal segments short, broader than long ; anterior antennae little 
longer than body. Fifth feet small, two-jointed (Sars), or three-jointed (Farran), without 
spines on inner margin ; last joint with three small apical spines. (Atlantic. Ireland.) 
14. X. TYPIGUS. 
AmaUoplwra typica, Scott, Tr. Linn. Soc. (2), YI. (1894), p. 54. 
Only the i known; 27 mm. long ; anterior antennae, twenty segments ; right 
fifth foot short and three segments, left like that of X. agilis. 
o 
VOIi. IV. 
