SYSTEMATIC REPORT 77 



St. 2065. 4. v. 37 (day). South-west of Sierra Leone, 1600-1050 m., 1 o\ with large parasite, 18 mm. (Colour note, 



'Orange pink'.) 

 St. WS 996. 12. iii. 50 (day). Open ocean west of Orange River estuary, 1000-750 m., 1 imm. $, in two pieces, 



12 mm. (Benguela Current Survey). 



Remarks. This species is widely distributed in the warmer waters of the Atlantic Ocean from Britain 

 in the north to the south of South Africa in the south and has not been taken in any ocean other than 

 the Atlantic. 1 



With the specimens from stations 2063 and 2064 there is a colour-note ' deep orange ' and with the 

 specimen from station 2065 a colour-note 'orange pink'. W. M. Tattersall (1951, p. 56) records that 

 one bottle containing specimens of B. microps from the West Atlantic, to the east of New York, had 

 a label ' coloured orange '. 



Boreomysis tattersalli sp.n. 

 (Fig. 12A-G) 

 1939 Boreomysis microps Tattersall, p. 231, figs. 



Occurrence : 



St. 1585. 1. v. 35 (night). On equator, Western Arabian Sea, 1400-700 m., 1 $ not quite adult, 13-2 mm. 

 St. 1587. 3. v. 35 (night). Western Arabian Sea, north of equator, 1250-800 m., 1 badly damaged ? and 1 $ not 

 quite adult, 14-8 mm. Type. 



Description. Carapace very short anteriorly; anterior margin sinuous, being mostly convex 

 but concave distally forming an acute apex which extends forward almost as far as the anterior 

 margin of the eyes (Fig. 12 A and C). Last abdominal somite unusually long, measuring very nearly 

 as much as the third, fourth and fifth somites together. Antennular peduncle rather long and slender ; 

 first segment longer than the second and third segments together with a well-developed setose tubercle 

 on the middle of its dorsal surface ; base of the outer flagellum swollen and armed with very long 

 plumose setae (Fig. 12 A). Antennal peduncle robust, somewhat shorter than the antennular peduncle; 

 scale short, extending for one-fifth of its length beyond the antennular peduncle; 3! times as long as 

 its greatest breadth; spine terminating the unarmed outer margin very long, equal in length to the 

 apex (Fig. 12 A, B). Eyes moderately large, set widely apart; eyestalks somewhat barrel-shaped 

 with a well-marked short ocular papilla on the dorsal surface ; cornea a little wider than the eyestalks 

 and situated terminally. First thoracic appendage similar to that of B. microps. Second thoracic appendage 

 with the distal third of the inner margin of the carpo-propodus concave with the proximal end of the 

 emargination produced into a blunt ' hump ' which is armed with a group of five or six long plumose 

 setae but with no spines ; dactylus, armed along its inner margin with a close graduated row of spinous 

 spines, bending inward to fit into the concavity of the carpo-propodus to form a strong sub-chela (Fig. 

 12 D, E). Remaining thoracic appendages rather slender and similar in form to those of B. microps. 

 Uropods. Proximal unarmed portion of the outer margin of the exopod one-tenth of the total margin 

 and marked distally with a single slender spine; endopod slightly longer than the telson, bearing 

 a single long slender spine on the under side of the inner margin just distal to the statocyst (Fig. 12 F). 

 Telson longer than the last abdominal somite, 3! times as long as broad at the base; lateral margins 

 nearly straight so that the telson appears broader and is not so ' waisted ' as in B. microps and B. ros- 

 trata ; armed along the distal three-fourths of their length with a large number of spines which are 

 arranged in series with eight or nine very long spines on each side and groups of graduated smaller 

 spines in the spaces between them. Cleft less than one-sixth of the telson in depth, armed with 



1 Specimens from the Central Arabian Sea recorded by Tattersall (1939, p. 231) as microps are here referred to a new 

 species, tattersalli (vide infra). 



