1893.] MR. G. C. BOUllNE ON NEW COPEPOBA. 16") 



lateral setae. Mandible stout, the palp well developed, the basal 

 joint produced in a sharp process, the outer joint bearing three 

 terminal and one lateral seta. First pair of feet having the inner 

 branch 3-jointed, the proximal and distal joints subequal in length, 

 the middle joint rather more than half the length of the other two ; 

 all three joints denticulate on their outer margins. The outer 

 branch reaches as far as the first third of the distal joint of the 

 inner branch, and is provided with two terminal geniculate setae and 

 a stout external spine on each joint. Inner branch of the 2nd, 

 3rd, and 4th swimming-feet 2-jointed, the proximal joint mmute ; 

 outer branch 3-jointed, each joint denticulate along its outer 

 margin and bearing a powerful spine. Basal joint of the fifth pair 

 of feet broad, the inner segment bearing four stout plumose setae. 

 The second joint ovate, somewhat elongate, bearing three plumose 

 terminal setae and three external marginal spines, of which the 

 middle is twice tlie length of the other two. Posterior margin of 

 the first abdominal segment strongly denticulate dorsallj, the two 

 succeeding segments denticulate ventrally. Furca short; caudal 

 eetse minutely aculeate and half as long as tlie whole body. 



This is a well-marked species, agi-eeing with C. northumhricus 

 and C. trispinosus in the characters of the 2nd, 3rd, and 4th 

 swimming-feet, which are two-jointed, and in the nine-jointed 

 first antennae ; but differing from both in the form of the mandible- 

 palp, in the inner branch of the second antenna), iu the proportions 

 of the first pair of swimming-feet, and in the characters of the 

 fifth pair of feet of the female. 



Fam. Ctclopid^. 

 Cyclops AraiCANUs, n. sp. (Plate VI. figs. 8-11.) 



Cephalothorax ovate, evenly rounded in front. The first and 

 second free thoracic segments of equal length, the third about two- 

 thirds the length of the two preceding segments. Abdomen long 

 and narrow, its length, not including the furca, equal to the 

 four free thoracic segments. The first abdominal segment in the 

 female long, equal in length to the three succeeding segments. 

 The last abdominal segment finely denticulate on its posterior 

 margin. Furcal segment equal in length to last two abdominal 

 segments. Of the caudal setae the two outermost are short, the 

 internal median seta very long, equal in length to the whole 

 abdomen and the last two thoracic segments. 



The first antennae of the female 12-jointed, rather shorter 

 than the first joint of the cephalothorax. First antennae of the 

 male 14-jointed, the basal joint equal in length to the next six 

 joints. Hinge-joints between the 7th and 8th and 12th and 13th 

 joints; the 9th to the 11th joints inclusive swollen. Mandible- 

 palp consisting of a well-developed basal piece bearing two long 

 and one short seta. Maxillae, maxillipeds, and swimming-feet as 

 in C. orientcdis. Fifth pair of feet rudimentary, resembling those 

 of G. O'ientalis. 



