CYAMIDAE 309 



Gnathopod i, 5th joint ovate with rounded bulge on inner margin, similar in both 

 sexes. Gnathopod 2, 5th joint very massive, outer margin semicircularly convex, inner 

 margin short, with two large teeth fairly close together, the one near the hinge obscurely 

 bifid, similar in the two sexes, but the teeth closer together in the ?. 



Peraeopods 5-7 very strong and broadly expanded, 2nd joint with distal anterior 

 corner not forming a pointed tubercle ventrally, 3rd feebly expanded, postero-inferior 

 angle of 4th rounded-quadrate. 



Branchiae double on both segments 3 and 4, about equal in length to peraeon seg- 

 ments 2-6 together, accessory appendages in 3 about equal to head plus 1st segment, 

 single on segment 3, double on segment 4; absent in ?. In a juvenile S 4 mm. long, 

 there is a single stout, fairly long branchia on both segments 3 and 4, and a smaller one 

 developing at its base, with very small accessory appendages; in a juvenile c? 2-5 mm. 

 long, there is only a single short branchia on each segment. In the latter specimen the 

 2nd gnathopod already has the characteristic teeth developed. 



Length : ^ up to 16 mm., ? up to 12 mm. 



Remarks. This species, with which P. gracilis seems invariably to occur, is recorded 

 from the head region of the Southern Right Whale (Baloena austrolis), and by Liitken 

 also from the North Pacific Whale {B.japonico ?). 



Cyamus balaenopterae, Brnrd. (Fig. 171). 

 Barnard, 1931, p. 430. 



Occurrence: 1. Whale no. 867. Saldanha Bay. Blue Whale. 2 S3, 7 immat. ??, 1 juv. 



2. Whale no. 948. Saldanha Bay. Fin Whale. 2 <$<$, 5 ?? (2 with embryos), 1 juv 



3. Whale no. 961. Saldanha Bay. Blue Whale. 1 S, 5 immat. $$. 



4. Whale no. 1096. Saldanha Bay. Fin Whale. 6 SS, 3 ?? (1 ovig.), 1 immat. $, 

 1 juv. Types. 



5. Whale no. D 19. Durban. Fin Whale. 11 <$<$, 8 ?? (mostly immat.). 



Description. General outline of peraeon in dorsal view narrow, parallel-sided in S, 

 ovate in ?. Head parallel-sided, completely fused with 1st segment, which is rounded 

 laterally. Segment 2 with prominent neck in front, posterior margin sloping. Segments 

 3 and 4 lozenge-shaped in <$, not much broader than long; in ? considerably broader 

 than long, the antero-lateral angle of segment 4 produced in a rounded lobe. Segments 

 5 and 6 triangular or chevron-shaped. Segment 7 subcordate. Pleon with an unusually 

 well-developed pair of oval processes. 



On ventral surface in $ a pair of oblong, inwardly directed processes on segment 5, 

 and a pair of pointed tubercles on both segments 6 and 7 ; in <S only the paired tubercles 

 on segments 6 and 7, smaller than in $. 



Antenna 1 nearly as long as head plus segments 1 and 2, shorter in $, 1st joint subequal 

 to head, the other joints successively shorter. Antenna 2 extending about half length of 

 1st joint of antenna 1 . 



Maxilliped with fully-developed palp in adult. 



Gnathopod 1, 5th joint ovate, with prominent rounded tooth on inner margin. 



