SYSTEMATIC REPORT 159 



St. 980. 15. x. 32 (night). Between Falkland Is. and South America, 104-0 m., 1 adult <J, 22 juv. (In the juvenile 



specimens the eyes appear to be very red.) 

 St. WS 211. 29. v. 28 (day). North of Falkland Is., 161-174 m., 1 imm. ?. 

 St. WS 219. 3. vi. 28 (day). North-east of estuary of River Desire, South America, 116-114 m., 96 juv. (In very 



bad condition.) 

 St. WS 220. 3. vi. 28 (dusk to dark). East of estuary of River Desire, 108-104 m -> 4 adu l l c?c?> 9 breeding $?, 



30 juv. 

 St. WS 222. 8. vi. 28 (day). South-west of estuary of River Desire, 100-106 m., 3 small juv. 

 St. WS 226. 10. vi. 28 (day). North-west of Falkland Is., 144-152 m., 4 <$$, 11-5 mm., 2 juv. S3, 2 adult $? 



(1 ovig.), 9 juv. $?. 

 St. WS 233. 5. vii. 28 (day). North of Falkland Is., 185-175 m., 1 adult ?. 

 St. WS 243. 17. vii. 28 (dusk to dark). West of Falkland Is., 144-141 m., 2 adult SS, 2 adult $?, largest 12 mm., 



2 juv. S 6*> fragments. 

 St. WS 758. 12. x. 31 (night). North of Falkland Is., 94-0 m., 6 adult <$<$, 11 breeding ?$, largest 12-4 mm. 

 St. WS 767. 19. x. 31 (night). East of Gulf of St George, South America, 98(-o) m., 3 <$$, 5 ??, 4 juv. 

 St. WS 781. 6. xi. 31 (day). North of Falkland Is., 148 m., 2 adult $$. 

 St. WS 782. 4. xii. 31 (day). North of Falkland Is., haul A, 141-146 m., 1 ovig. $. 



St. WS 786. 7. xii. 31 (day). East of Santa Cruz, South America, 134-119 m., 1 adult S, 3 adult $$, largest 9-5 mm. 

 St. WS 787. 7. xii. 31 (day). East of Port St Julian, South America, 106-110 m., 3 adult SS, 15 ?? (some ovig.), 



fragments. 

 St. WS 798. 20. xii. 31 (day). South-east of Gulf of St George, 49-66 m., 5 adult $$, 2 juv. $?. 

 St. WS 801. 22. xii. 31 (day). North of Falkland Is., 165-165 m., 6 adult $$, 15 ?$, breeding, fragments. 

 St. WS 802. 5. i. 32 (day). North of Falkland Is., 2 hauls: (i) haul A, 128-132 m., 5 adult S3, 5 adult ?$> x J uv -i 



(ii) haul B, 132-139 m., 8 £<$, 12 $$, breeding, largest n-6 mm., 3 juv. $$. 

 St. WS 806. 7. i. 32 (day). North-west of Falkland Is., 130-123 m., 13 adult <$£, 19 adult ?$, some ovig., largest 



io-8 mm., many fragments. 

 St. WS 809. 8. i. 32 (day). Off Cape S. Francisco de Paula, South America, 108-104 m., 6 adult S3, 8 adult $?, 



4 juv. $$, 1 juv. S- 

 St. WS 816. 14. i. 32 (day). West of Falkland Is., 150-150 m., 2 adult $<$, 11 adult $?, breeding, fragments. 

 St. WS 837. 3. ii. 32 (day). Off eastern end of Strait of Magellan, 102-102 m., 2 adult S3, 1 juv. S, 6 adult 9$ 



(3 ovi g-)> 1 J uv - ?• 



Remarks. Up to the present this species has been known only from the types — two poorly pre- 

 served immature males taken in 1902 off the Falkland Isles — and from three specimens captured by 

 the Tierra del Fuego Expedition in April 1896. 



The present specimens agree so closely with Hansen's figures and description (19 13, p. 16) that 

 I have no hesitation in referring them to his species. There is, however, one striking feature which 

 Hansen did not mention. In all the specimens I have examined in the Discovery material, the inner 

 margins of the endopods of the uropods are armed from the region of the statocyst to within a short 

 distance of the apex with an extremely close row of regular spines, which are smaller proximally and 

 increase evenly in size distally. These spines are present in quite small immature specimens as well 

 as in the adults, and it is most surprising that so meticulous a worker as Hansen could have over- 

 looked them. I have not had an opportunity of examining the type specimens, but in view of the very 

 close agreement in all other respects of my specimens with the published description of M. acuta, I 

 venture to suggest that the presence of these spines is a regular character of the species (Fig. 39 H). 



Although Hansen had an adult male in the Tierra del Fuego material he did not describe or figure 

 the male pleopods. I am now able to record that in the fourth pair the exopod, as in other species 

 of the genus, is modified being longer and stouter than the endopod and bearing at its tip a single 

 strong barbed non-plumose seta (Fig. 39 G). 



M. acuta may readily be recognized by the acutely pointed apex of the antennal scale (Fig. 39 A) 

 and by the long linguiform telson, which is fully twice as long as the breadth at the base (Fig. 39 H). 



