92 DISCOVERY REPORTS 



The endopods of the third to the eighth thoracic appendages are long and slender, the carpus 

 articulated with the two-segmented propodus : this articulation is usually oblique, but may be trans- 

 verse ; nail setiform. The male genital organ on the eighth thoracic appendage in most species is long 

 and tubular, unarmed except for a strong curved bristle. The pleopods of the male are well-developed 

 and show little modification. In some species the rami of the fourth pair may be of unequal length 

 and there may be some modification of the setae on one or both of them. 



The endopods of the uropods are usually considerably shorter than the exopods and generally bear 

 no spines along their inner margins, though there may be a single spine in the region of the statocyst. 

 The telson is entire and linguiform, usually short with an obtusely rounded or truncate apex, the 

 lateral margins usually armed with a limited number of small spines, which are confined to the (at 

 most) distal two-thirds of the margins. The apex of the telson is armed with from two to five pairs of 

 long spines and there is usually a pair of median setae. There are, however, one or two species in 

 which the telson does not conform to the above description and the safest guide to the genus is the 

 form of the eyes. 



The identification of the species in this genus in the Discovery material has given me a great deal of 

 trouble and I have come to the conclusion that a considerable amount of individual variation in each 

 species must be accepted unless a large number of new species are to be instituted. In most species the 

 animals are not particularly common or, at least, they are not gregarious in habit for the number taken 

 at each station rarely exceeds one or two. As the specimens are not as a rule in very good condition, 

 I have referred many which do not agree in all points to the same species and have discussed their 

 characters later when describing the species. 



Pseudomma armatum Hansen, 19 13 



191 3 Pseudomma armatum Hansen, p. 12, figs. 

 1930 Pseudomma armatum, Rustad, p. 7. 



Occurrence : 



St. 42. 1. iv. 26 (night). Off Cumberland Bay, South Georgia, 204-120 m., 2 $$, 18 mm. 



St. 45. 6. iv. 26 (day). East of Jason Light, South Georgia, 270-238 m., 5 <JcJ, 3 ??> largest 18 mm., 4 juv. 



St. 123. 15. xii. 26 (day). Off Cumberland Bay, South Georgia, 250-230 m., 1 <J, 8 $?, 18-20-5 mm. 



St. 142. 30. xii. 26 (day). East Cumberland Bay, South Georgia, 273-88 mm., 16 <J<J, 73 ?$, largest 19 mm., 

 2nd tube, 2 <$<$, 6 $$, largest 12 mm., all imm. 



St. 148. 9. i. 27 (day). Off Cape Saunders, South Georgia, 148-132 m., 1 <3\ 20 mm., 1 <J juv. 



St. 154. 18. i. 27 (day). Jason Harbour to Larsen Point, South Georgia, 160-60 mm., 18 <$$, 16-18 mm., 8 £<$ juv., 

 63 ?$, 18-20 mm. (many ovig.), 18 ?? juv. 



St. 162. 17. ii. 27 (day). Off Signy Is., South Orkneys, 320 m., 1 (J, 16 mm. (juv.), 1 ovig. 9, 22-5 mm., 2 non- 

 breeding $$, 17-5 mm. 



St. 167. 20. ii. 27 (day). Off Signy Is., South Orkneys, 344-244 m., 8 £<$, juv., 16-19 mm., 2 ??, 19-20 mm., with 

 empty brood pouches, 3 ?? juv. 16 mm. 



St. MS 68. 2. iii. 26 (day). East Cumberland Bay, 247-220 m., 3 ??, largest 19 mm. (ovig.), 21 juv. 



Remarks. These specimens are larger than any of this species which have hitherto been recorded. 

 Males of 16-17 mm. have well-developed lobes on the antennular peduncles, but these are not hirsute 

 and each pleopod is not more than three-quarters of the length of the succeeding abdominal somite. 

 Females of 16 mm. are obviously immature. The largest specimen is an ovigerous female from station 

 162 measuring 22-4 mm. 



There is some variation in the length of the apex of the antennal scale. In all specimens from 

 South Georgia it is markedly longer than the tooth terminating the outer margin of the scale (as in 

 P. belgicae), but in the specimens from the South Orkneys the apex and the terminal tooth are almost 



