20 



A REVTSIOX OF THE BRITISH SPECIES OF 



slightly constricted in front and not wider than the abdomen ; 

 first segment very large, occupying E- 



about two-thirds of the entire length 

 of the cephalothorax. Abdomen only 

 very slightly tapering backwards, 

 its first segment much the longest. 

 Caudal rami about thrice as long as 

 broad, closely approximated and not 

 at all divergent ; outermost seta short, 

 spine-like, nearly as long as the f urea, 

 innermost about twice as long, very 

 slender and inconspicuous ; of the two 

 median setae, the inner is the longer, 

 being more than equal in length to 

 the whole abdomen ; the outer is about 

 two-thirds as long; the plumose char- 

 acter so delicate as to be scarcely 

 discernible ; the lateral setae are short, 

 and arise a little behind the middle of 

 the furca. Anterior antennae slender, 

 of nearly equal thickness throughout, Cyclops ma s noeta ™ s > <**•■■ 



I. Female, seen from above x 60. 

 and reaching, when reflexed, almost n - Anterior antenna of same. 



III. Labrum. 



to the anterior margin of the abdo- IV - Foot of fifth pair. 

 men, rather sparingly clothed with setae, though the fourth joint 

 bears one of remarkable length : the length of the joints may 

 b e formulated thus : 



1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 

 16 5 4 10 6 3 12 18 14 11 12 12 

 The rami of the first four pairs of feet are all three-jointed, the 

 spines of the external rami very delicately pectinated. The fifth 

 foot is one- jointed and bears three setae, the apical seta more 

 than twice as long as the others :. the side of the last thoracic 

 ring near the margin of the fifth foot bears a fringe of fine hairs. 

 Length *85 mm. 



For this interesting species I am indebted to my friend the 

 Bev. Dr. Norman, F.R.S., by whom it was taken "in a ditch at 

 the end of Lochaber Loch, Kirkcudbrightshire," in 1885. The 



85 



