[fraser] COPEPODS PARASITIC ON FISH 53 



In the appendages the main differences, as compared with the 

 female, are in the second antennee, the first maxillae and the maxilli- 

 peds. The basal joint of the second antenna is corrugated and the 

 basal portion of the claw has also a ring of striœ and a small curved 

 spine or claw near- the bend; the main claw has a smaller, accessory 

 claw oh each side. The first maxilla is quite different in appearance to 

 that of the female; the portion that corresponds to the outer ramus 

 is blunted and in place of the inner ramus there are two spine-like 

 projections, the one larger and stronger than the other. The terminal 

 joint of the maxilliped is longer and more slender, relatively to the 

 basal joint than it is in the female. 



Total length 1 • 8 mm., length of carapace 1 • 23, width 1-16, length 

 of genital segment 0-34, width 0-42. 



Colour: Bright flesh colour in living specimens but this colour 

 disappears in preserved specimens. 



{hreviventris is self-explanatory.) 



Found attached to the mucous membrane of the roof of the 

 mouth of the ling cod, Ophiodon elongatus. 



Lepeophtheirus hospitalis new species 

 PL. IV, Figs. 47-58. 



Female: Body short and stout. Carapace ovate, narrower 

 anteriorly, length slightly greater than breadth; lateral grooves well 

 in from the margin; transverse groove well forward, dividing the cara- 

 pace into nearly equal parts; posterior sinuses of medium depth and 

 width; lateral lobes broad; median lobe a little less than half the 

 width of the carapace. Free thoracic segment not distinctly separated 

 from the genital segment, over half as broad as the median lobe. 

 Genital segment much broader than long, rounded anteriorly ^nd 

 posteriorly; posterior lobes not showing dorsally. Abdominal segment 

 undivided, short, about one-fourth the length of the genital segment, 

 of nearly uniform width. Anal laminae not large, well separated, 

 six setae on each lamina but two of them very small; a third one is 

 much shorter than any of the other three. The egg strings are long 

 and slender, a little longer than the carapace, with over 50 eggs in 

 each string. 



First antennae short and stout, not projecting far past the cara- 

 pace. Second antenna with a small spine at the base, the distal 

 portion slender and abruptly curved. Maxillary hook, short, taper- 

 ing. First maxilla with a broad base that projects laterally much 

 farther than the outer ramus, but medially is almost in line with the 



