SYSTEMATIC REPORT i39 



Distribution. This species is widely distributed in the warmer waters of the Atlantic and has once 

 been taken in the Indian Ocean. It was recorded from five stations in equatorial waters in mid-Atlantic 

 (Ortmann, 1893); from off the west of Cape Town (Stebbing, 1905); Gulf of Guinea, west of Cape 

 Town, west of Cape Verde Islands (Zimmer, 191 4) ; Gulf of Guinea, Atlantic, west of Angra Pequena 

 and north-west of Cape Town, east of Maldives (Indian Ocean) (Illig, 193°)- 



In the Discovery collections, it occurred at fourteen stations in the Atlantic, between 14 N. and 

 38 S. Fragments of a male from station 1585, to the north of Madagascar, probably belong to this 

 species, for the form of the spines and the shape and size of the antennal scale are as in Caesaromysis 

 hispida, but the telson has more spines on the lateral margins than I have seen in this species. In the 

 absence of the thoracic endopods and part of the thorax, I am unable to say whether there was a normal 

 exopod on the first thoracic appendage. It may be a specimen of Echinomysis chuni, a species which 

 has been recorded from these waters. 



Except for one record by Ortmann, in which he states that a closing net fishing between 200 and 

 400 m. was used, the species, apart from the Discovery material, has always been taken in vertical or 

 oblique hauls from depths of 3000 m. to the surface. It has never been taken at the surface. During 

 the Discovery investigations, it was captured on a number of occasions in closing nets and we are now 

 able to say with more precision at what depths the animals were living. It appeared in two hauls 

 taken at station 100 C in closing nets fishing at 260-310 m. and at 2500-2000 m. and was also taken in 

 a closing net at station 673 fishing at 1000-750 m. It would therefore appear to be usually a deep- 

 water form. The shallowest water in which it was taken was at station 282, 23o(-o) m. 



Caesaromysis hispida has never been taken in large numbers, rarely more than one or two at a time 

 and is obviously not a gregarious form. 



Genus Arachnomysis Chun, 1887 



Arachnomysis leuckartii Chun, 1887 



1887 Arachnomysis leuckartii Chun, p. 33, figs. 



1896 Arachnomysis leuckartii, Chun, p. 169, figs. 



1905 Arachnomysis leuckartii, Thiele, p. 445, figs. 



191 1 b Arachnomysis leuckartii, Tattersall, p. 56. 



1914 Arachnomysis leuckartii, Zimmer, p. 399. 



1930 Arachnomysis leuckartii, Illig, p. 469, text-figs. 



1 95 1 Arachnomysis leuckartii, Tattersall and Tattersall, p. 282, figs. 68-9. 



Occurrence : 



St. 270. 27. vii. 27 (night). West of Benguela, 20o(-o) m., 1 ?, 7 mm. 



St. 282. 12. viii. 27 (night). Gulf of Guinea, 30o(-o) m., 1 very small juv. 



St. 290. 24. viii. 27 (dawn). West of Sierra Leone, ioo(-o) m., 1 imm. $, 6 mm. 



St. 694. 10. v. 31 (night). Mid-Atlantic, south-south-west of Cape Verde Is., 2io(-o) m., 1 ?, 6-8 mm. with very 



small brood pouch. 

 St. 699. 14. v. 31 (night). West of Cape Verde Is., 250-0 m., 1 small juv. ?. 

 St. WS 986. 10. iii. 50 (day). West of Spencer Bay, South-west Africa, 50-0 m., 1 adult ?, 5-6 mm. (Benguela 



Current Survey). 

 Distribution. This species was for many years thought to be confined to the Mediterranean, where 

 it had been recorded on many occasions from deep water (1050-2000 m.). Later it was recorded 

 from the East Atlantic slope off the south-west of Ireland. Illig (1930, p. 469) recorded it from the 

 Gulf of Guinea (2000 m.); west of Angra Pequena (500 m.); South Atlantic and west of Chagos 

 Islands (2000 m.); Seychelles (1500 m.); west of Arimante Islands (2000 m.); east of Ras Hafun 



(1500 m.). 



18-2 



