538 Ake nordenstam 



upper lip triangular with acute apex. 



Mandibles typical of the genus. First joint of the palp about ^S) 3''d 

 joint about 73 of the length of the 2nd. The relation between the joints is 

 5:15:11. 1st joint almost without setae. 2nd joint with 3 setae in a longi- 

 tudinal row on the distal half of the joint. 



Maxillipeds normal, with a little tip at the apex, not distinct as a joint. 



1st pereiopods (fig. 6 a). The 2nd joint a little longer than the 3rd, 4th joint 

 about sublunate, the 5th triangular; 6th joint narrowly oval, anteriorly decreasing 

 in width. The lower proximal angle close to the carpus is tooth-like and 

 pointed. From this tooth a faint carina extends near the anterior edge. The 

 anterior edge is convex, the posterior edge slightly concave (almost straight). 



2nd and ^rd pereiopods (fig. 6 b). Propodus with about 10 short and 

 strong and some long and slender setae on the lower margin. 



/f.th — Jth pereiopods. Merus with its upper distal corner produced and 

 acute and furnished with a seta at the apex. Carpus with distal margin almost 

 rounded, only with the upper distal corner very slightly angular, but not produced. 



In the 6th pereiopod (fig. 6 c) the carpus has 6 strong setae and some 

 slender ones on the lower margin, and the propodus has 4 setae on the lower 

 margin. The 5th and 7th pereiopods are also about like as the 6th in this respect. 



1st pleopod (fig. 6 d). Basipod with the medio-distal corner produced, 

 rounded. Exopod single-jointed, but a very faint limit seems to be slightly 

 indicated at the median side. Distal end broadly rounded. 



2nd pleopod (fig. 6 e). Exopod two-jointed. First and second joints 

 are of about equal length. Endopod with a very faint limit. 



^rd — §th pleopods. Both rami faintly two-jointed, lateral margins with a 

 faint incision between the joints, distal margin of 2nd joints with setae. 



Uropods (fig. 6 f). The endopod reaches about as far as to the end of 

 the telson. First joint with a row of setae on the lateral margin; second 

 joint oval, a little longer than it is broad; dorsally it is concave, ventrally con- 

 vex. Exopod with its outer lateral margin sinuated near apex. 



Paranthura nana n. sp. — PI. 20, fig. 6; text figs. 7, 8. 



One female, with empty marsupium, length 4,5 mm. 



Loc. Juan Fernandez, Masatierra, 30 — 40 m, calcareous algae. 



Description. 



Head rectangular, seen from above slightly longer than wide (a little 

 longer than shown in PI. 20, fig. 6). The anterio-lateral corners rounded, very 

 slightly more produced anteriorly than the small triangulate rostrum. Anterior 

 margin bisinuated. Eyes small rounded, dark brown, composed of 6 — 8 ocelli. 



Thorax, ist segment a little longer than the other, 2nd— 4th segments of 

 about equal length, 5th is a little longer; 6th and 7th segments decrease in 

 length. The 7th segment is about as long as the abdomen without the telson. 



Ventral side on the first thoracic segment strongly carinated; on the 2nd 

 the keel is more flattened, the 3rd and 4th segments are ventrally vaulted. 

 Impressed line on the last 3 thoracic segments obscure. 



