16 Acootiostoma, Stomacontion, Hirondellea 



Pleon Segments 1 — 3 not carinate, 4**^ with depression foUowed by small 

 hump overhanging tbe followiug segments. P]yes small. Autenna 1 and 2 

 nearly as iu preceding species; flagellum 4-jointed, accessory flagellum 2-jomted. 

 Antenna 2 rather sliorter than antenna 1, flagellum 4-jointed. Mandible 

 with strap-sbaped secondary plate on left mandible, spine-row of 6 spinules, 

 and ciliated tract. Maxilla 1, palp small, acute, 1-joiuted. Maxillipeds, inner 

 plates sbort, 4*^ Joint of palp forming a small but very distinct, straight, 

 tapering flnger. Gnatbopod 2, 5**^ Joint a little sborter tban 6*^^. üropods 

 almost entirely devoid of spines. Telson sbort and broad, emarginate or a 

 little cleft, witb . 2 spines on eacb apex. L. 3 mm. 



Possibility that this may be the young of A. marionis. 



Entrance to the Strait of Magellan (Cape Yirgins). Depth 100 m. 



5. Gen. Stomacontion Stebb. 



1888 Acontiostoma (part.), T. Stebbing in: Rep. Voy. Challenger, «;. 29 p. 709 | 

 1899 Stomacontion (Sp. typ. : Acontiostoma pepinii), T. Stebbing in : Ann. nat. Hist., 

 ser. 7 V. 4 p. 205. 



Agreeing in general witb Acontiostoma (p. 15), but distinguisbed by 

 maxilla 1 witb palp 2-jointed, maxilliped witb 4*^1 Joint of palp rudimentary, 

 uropod 3 ending in a tubercular ramus. 



1 species. 



1. S. pepinii (Stebb.) 1888 Acontiostoma p. -^ A. her gueleni, T. Stebbing in: 

 ßep. Voy. Challenger, v. 29 p. 716 t. 32 (? or juv.); p. 720 t. 33 (c5) | 1899 A. p., 

 Stomacontion sp. typ., T. Stebbing in : Ann. nat. Hist., ser. 7 v. 4 p. 206. 



9 or juv. Peraeon broadly rounded. afterpart of pleon compressed. 

 Pleon Segment 3 dorsally rounded, rising above tbe 4*^ wbicb bas a deep 

 dorsal excavation, wbile tbe end is strongly upturned, witb tbe process rounded 

 bebind. Eyes very small. Antennae about as in Acontiostoma, but peduncle 

 of antenna 1 more robust, flagellum 5-joiuted, accessory flagellum 2-jointed. 

 Antenna 2, flagellum 4-jointed. Mandible witb 7 spinules and ciliated tract. 

 Maxilla 1, palp minute, 2-jointed. Maxillipeds, inner plates long, 4*^ Joint of 

 palp quite rudimentary. Gnatbopod 2, 5*^ and 6*'^ joints subequal. Peraeopod 5, 

 2*^ Joint at lower bind corner quadrate, tbe point a little incised. üropods 1 

 and 2, eacb witb subequal rami, uropod 3 witb a Single tubercular ramus. Telson 

 witb small apical notcb accompanied by spines and cilia. L. 2*5 — 7-5 mm. — 

 (S . Pleon Segment 3 ending dorsally in a little upturned tip. Eyes large, 

 oval. Antenna 1 distinguisbed by baving 1^* Joint of 5-jointed flagellum 

 enlarged and fringed witb filaments, accessory flagellum 2-jointed. Antenna 2, 

 flagellum 4-jointed. Mandible. witb small bifid accessory plate on tlie left; 

 2 or 3 spinules seen, but no ciliated tract. Gnatbopod 2, 5*^ Joint longer tban 

 6*^ Peraeopod 5, 2^ Joint a little rounded at lower bind corner. üropods 1 

 and 2, eacb witb tbe rami unequal. uropod 3 witb one tubercular ramus. 

 Telson witb apical notcb, and' spinules. L. 7-5 mm. 



Royal Sound [Kerguelen Island]. Depth 50 m. 



6. Gen. Hirondellea Cbevreux 



1889 Hirondellea (Sp. un.: H. trioculatä), Chevreux in: Bull. Soc. zool. France, 

 ^. 14 p.285 i 1893 E., A. Della Valle in: F. Fl. Neapel, v.20 p. 836 ] 1893 Mirondella 

 (laps.), J. V. Carus in: Zool. Anz., Regist. 11 — 15 p. 142. 



