ii8 DISCOVERY REPORTS 



Bouvier lists seven ^ species of Tanystyhmi, and two- other species have since been 

 described, namely T. oedinotwn, Loman (1923, p. 29), and T. ornatum, Flynn (1928, 

 p. 33). Several species are imperfectly known or known from a single specimen only 

 (e.g. T. hoekiimum, Schimk., T. chierchiae, Schimk., T. cakirostre, Schimk., and 

 T. oedinoiiim, Loman). Therefore it has not been thought advisable to give a key to the 

 determination of species not found in Antarctic and sub-Antarctic waters. The forms 

 with a four-jointed palp are not represented in the Discovery collection, so that the 

 question of the validity or non-vaUdity of the genus Clotenia, Dohrn, cannot be 

 discussed here. 



Two Antarctic species, T. styligeriim, Miers, and T. pfefferi, Bouvier, have recently 

 been described elsewhere (Gordon, 1932 a, p. 87). 



Key to the determination of the Antarctic and sub-Antarctic species : 



Palp with seven segments : 



Long setose spines on walking legs ; palpal segments 2 and 4 subequal, long; abdomen long, 



extending beyond the second coxa of the last leg T. styligerum, Miers 



No long setose spines on walking leg ; palpal segment 2 longer than 4 ; abdomen extending to 

 distal end of first coxa [a low, wide tubercle on dorsal surface of body, between ocular 

 tubercle and abdomen] T. oedinotum, Loman 



Palp with six segments, or with seventh segment more or less fused with sixth. 



Walking leg rather slender, second tibia nearly twice the sum of tarsus and propodus 



(I7S-I-9 : i) T. pfefferi {typical form) 



Walking leg relatively shorter and more robust; second tibia only about 1-25 times the sum 



of tarsus and propodus T. pfefferi {Falkland I. var.) 



Tanystylum styligerum, Miers (Fig. 65 b). 



Nymphon styligerum, Miers, 1875, p. 76. 

 Tanystylum styligerum, Miers, 1879, p. 213, pi. xi, figs. 9-9 d. 

 Tanystylum kentrodes, Loman, 1923, p. 28, fig. E, 1-4. 

 Tattystyhmi longicaiidatum , Hodgson, 1907 fl, p. 13, figs. 4-6. 

 Tanystylum styligerum, Gordon, 1932 a, p. 88. 



St. 53. 12. v. 26. Port Stanley, East Falkland Islands, hulk of 'Great Britain', 0-2 m. Mussel 

 rake: 14 specimens, adults and young, "sorted from washings from Hydroids and Mytilus clumps" 

 (with Achelia parvula and Austrodeeus glacials). 



Remarks. The specimens agree well with the co-types of T. styligerum (Gordon, 

 1932 a, p. 88). Several specimens resemble T. kentrodes (Loman, 1923, p. 28) in 

 having a single long spine on the tubercle borne by each of the three anterior lateral 

 processes. In other specimens there are 1-3 spines on each tubercle. The anterior 

 border of the cephalon, measured to the outer rim of the sockets for the palps, is a little 

 less (c?) or a little more (?) than half the width across the second lateral processes. 



The ocular tubercle is more slender and is set further forward than that represented 



1 Excluding T. hoekiaman, Schimk.; T. longicaudatim , Hodgson, however, appears to be a synonym of 

 T. styligerutn, Miers. 



2 T. kentrodes (Loman, 1923, p. 28) is also a synonym of T. styligerum. 



