Synurella, Paracrangonyx 369 



1. S. ambulans (Fr. Müll.) 1846 Gammarus a., Friedr. Müller in: Arch. Naturg., 

 V. 12 1 p. 296 t. 10 f. A — C I 1872 Crangonyx a., A. Boeck, Skand. Arkt. Amphip., 

 V. 1 p. 52 I 1879 Goplana a., Wrzesniowski in: Zool. Anz., v.2 p. 302 | 1888 6r. «., 

 T. Stebbing ia: Rep. Yoy. Challenger, t?.29 p. 217, 502 | 1893 G. a., A. Della Valle in: 

 F. Fl. Neapel, v. 20 p. 644. 



Close to S. polonica, perhaps identical with it. Back smooth. Head 

 without rostrum. Eyes tending to round. Antenna 1, the 2-joiiited accessory 

 flagellum very small. Uropod 3 very small. Telson cleft(?), appendages 

 Short, cylindrical, spinulose at apex. L. about 4-5 mm. 



Near Greifswald, and near Berlin. 



2. S. polonica Wrzesn. 1877 S. p., (Wrzesniowski in:) H. Hoyer in: Z. wiss. 

 Zool., *).28 p.403 I 1879 Goplana p., Wrzesniowski in: Zool. Anz., v.2 p.300 | 1888 G.p., 

 T. Stebbing in: Rep. Voy. Challenger, j;.29 p. 472, 501, 503 | 1890 G.p., Wrzesniowski 

 in: Z. wiss. Zool., v. 50 p. 639; t. 28 f. 13; t. 30 f. 5, 14; t. 31 f . 3 | 1893 G. p., A. Della 

 Valle in : F. Fl. Neapel, v. 20 p. 646. 



Body rather stout, back broad, rounded. Head, front corners very 

 prominent. Eyes of moderate size, deep brown black, pigment somewhat 

 irregularly distributed, crystalline cones few. üropod 3, peduncle broad, 

 the Single ramus very short, with 1 spine at the apex. Telson apically 

 emarglnate. In both sexes gnathopod 2 and peraeopod 1 have a pair of 

 cylindrical accessoiy branchiae on the front rim of fleshy part of side-plates, 

 and to peraeopods 4 and 5 and to the fi'ont rim of pleon segment 1 

 similar but simple accessory branchiae are attached. In the <S from gnathopod 2 

 to peraeopod 5 there are lamellar appendages homologous in Situation and 

 structure to the marsupial plates of the Q . Colour, ä green, Q brownish- 

 yellow, both with an irregulär patch of lemon-yellow on top of the head. 

 L. 9 6*5 mm, <3 smaller. 



Warsaw. In weedy ditcli. 



3. Gen. Paracrangonyx Stebb. 



1899 Paracrangonyx (Sp. typ.: P. compactus), T. Stebbing in: Tr. Linn. Soc. 

 London, ser. 2 «. 7 p. 422. 



Side-plates 1 — 4 shallow, not deeper than the rest. Eyes rudimentary. 

 Antenna 1 longer than antenna 2, accessoiy flagellum small. Upper lip 

 faintly emargiuate. Lower lip with small inner lobes. Mandible, molar 

 small, 3*^ Joint of palp subequal to 2*^. Maxiila 1, inner plate with 2 setae, 

 outer with 7 spines, palp 2-jointed. Maxilla 2, outer plate rather longer 

 and broader than inner. Maxillipeds, outer plates short, palp large. Gnatho- 

 pods 1 and 2 subchelate, 6*^* Joint oval, palm oblique. Peraeopods 1 and 2, 

 2'^ Joint naiTOwly ovate. Peraeopods 3 — 5, 2*^ Joint narrowly oblong. Pleo- 

 pods 1 — 3 slight, 1-branched. Uropods 1 — 3 short, biramous. üropod 3 

 with inner ramus very small. Telson entire. 



1 species. 



1. P. compactus (Chilton) 1882 Crangonyx c, Chilton in: N. Zealand J. 

 Sei., v.l p.44 I 1893 C. c, A. Della Valle in: F. Fl. Neapel, v. 20 p. 682 t. 60 f. 14 | 

 1894 C. c, Chilton in: Tr. Linn. Soc. London, ser. 2 v.Ö p. 220 t. 20 1 1899 Paracran- 

 gonyx c, T. Stebbing in : Tr. Linn. Soc. London, ser. 2 u 7 p. 422. 



Pleon rather deep, segments 1 — 3 not much longer than those of 

 peraeon. Head not rosti-ate, lateral corners rounded. Pleon segment 3, 



Das Tierreich. 2i. Lief. T. E. R. Stebbing, Amphipoda I. 24 



