AMPELISCIDAE 81 



Family AMPELISCIDAE 



Stebbing, 1906, p. 97. 



Strauss, 1909, pp. 20-36 (eye structure). 



Barnard, 1916, p. 132; 1925, p. 335; 1930, p. 329. 



Three of the four known genera are now found to be represented in the Antarctic. 

 The South African Triodos, Brnrd., was instituted to express the breakdown of the 

 generic definitions which up to that time were clear cut, though Byblis anisuropus, Stebb. 

 1908, showed a slight anomaly. The Antarctic fauna is now shown to possess a Haploops 

 with an expanded 2nd joint in peraeopod 5 as in Ampelisca and Byblis ; the type of a new 

 genus with rather distinctive features of its own, together with characters of Ampelisca 

 and Byblis; also two forms with simple branchiae, a character which is in conflict with 

 the hitherto accepted definition of the family. Finally, the Haploops which has been 

 brought to light by the ' Discovery ' has the lower pair of corneal lenses on the ventral 

 surface of the head, as in A. hemicryptops recently described from the Terra Nova 

 collection. 



Genus Ampelisca, Kroy. 



Stebbing, 1906, pp. 98, 721. 



Barnard, 1916, p. 132; 1925, p. 335; 1930, p. 329. 



Ampelisca eschrichtii, Kroy. (Fig. 37 a). 

 Chevreux, 1906, p. 20, fig. 11 ; 1913, p. 96. 



Occurrence:!. St. 42. South Georgia. 1924 mm. 



2. St. 144. South Georgia. 1 <$ 22 mm., 2 ovig. ?$ 21 and 25 mm., 6 juv. 10-1 1 mm. 



3. St. 180. Palmer Archipelago (160 m.). 3 $? 20-23 mm. 



4. St. 187. Palmer Archipelago. 2 ?$ 21 and 23 mm. 



Remarks. On the question of the identity of the northern and southern forms see 

 Chevreux (1906), Chilton (19 17, Joum. Zool. 

 Res., xi, p. 75) and Stephensen (1925, p. 140). 

 Stappers and Stephensen are able to dis- 

 tinguish macrocephala from eschrichtii and 

 these two species are very distinct in Sars' 

 figures. A fortiori I fail to see how it is "■ 



possible to include either acinaces or chiltoni in Fig> Th ° utline of head of : a - Am P e &™ eschrichtii, 



, ■ , ,.. rr,, , j 1 i- 1 Kroy.; b. hemicrvptups, Brnrd. 



eschrichtii. lhe more evenly rounded hind 



margin of the 2nd joint of peraeopod 5 and the stronger dorsal keel on pleon segment 4 



seem to be sufficient to distinguish the southern form, though in the opinion of some 



authors these may not constitute specific characters. I entirely agree with Stephensen. 



and think that a new name should be found for the southern eschrichtii. 



The 2nd joint of the mandibular palp is linear in the southern as in the northern form. 



Distribution. Palmer Archipelago, 60-200 m. 



