Niphargus * 407 



in: Ann. nat. Hist., ser. 2 u 12 p. 44 | 1855 iY. aquilex, Schiödte in: Ov. Danske Selsk., 

 p. 350 f. I 1888 N. a. (part.), T. Stebbing in: Rep. Voy. Ghallenger, ».29 p.l58, 287,304, 

 316,448,456 | 1890 N. puteanus var. vejdovskyi, Wrzesniowski in: Z. wiss. Zool., u 50 

 ]). 655 t. 27 f. 6, 9—11, 15; t. 28 f. 1—3; t. 30 f. 3 | 1893 N. subterraneus (part.), A. Della 

 Valle in: F. Fl. Neapel, ».20 p. 704 t. 38 f. 31— 34. 



Body long and narrow. Side-plates 1 — i not deeper than 5*^'. Pleon 

 Segments 1 — 3, postero-lateral corners rouuded. Eyes wanting. Antenna 1, 

 1^* Joint nearly as long as 2^^ and 3*^ combined, S^ about half as long as 2*^, flagellum 

 witli about 20 joints, accessory flagellum very small, 2-jointed. Antenna 2 

 much shorter but with longer peduncle, ultimate Joint of peduncle a little 

 shorter than penultimate, flagellum 7- or 8-jointed. Gnathopods 1 and 2, 

 5*^' Joint much uarrower than 6*^^, 6*'^ rounded triangulär, widening to the 

 palm, which is long, straight, defined by a spine at the obtuse angle. Peraeo- 

 pods 1—3 subequal, peraeopods 4 and 5 rather longer. Peraeopods 3 — 5, 

 2*^ Joint oblong oval. Uropods 1 and 2 very short, uropod 3 very long, 

 ospecially in ö, peduncle short, outer ramus very long, 2^ Joint in ö nearly 

 as long as 1***, in Q much shorter, inner ramus short, rudimentary. Telson 

 short, deeply cleft, apices obtuse. Colour whitish, pellucid. L. d reaching 

 20, 9 12-5 mm. 



Surope (south of England, St. Briac, Ijeyden, Cologne, wells in Bohemia (var. 

 üejdovsk^i), and other places). 



4. N. stygius (Schiödte) 1847 Gammarus s., Schiödte in : Ov. Danske Selsk., 

 p. 81 I 1849 NipJiargus s., Schiödte in: Danske Selsk, Skr., ser. 5 (-.2 p. 26 t. 3 | 1890 

 X. .s'., Wrzesniowski in: Z. wiss. Zool., ».50 p. 603, 620, 665. 



Body long and narrow. Side-plate 3 slightly deeper than 4**', 4*^ than 

 5*^'^. Pleon Segments 1 — 3, postero-lateral corners in figure slightly rounded. 

 Eyes wanting. Antenna 1, 1*^ Joint rather longer than 2^, 3*^ half as long 

 as 2<^, flagellum 16 — 25-jointed, accessory flagellum very small, 2-jointed. 

 Antenna 2 % as long as antenna 1, ultimate and penultimate joints of peduncle 

 subequal, flagellum 7 — 9-jointed. Maxiila 1 with 7 spines on the outer 

 plate, but figured with several setae on the inner plate and a great number 

 on the outer margin of the palp's 2^ Joint, peculiarities not to be acceptJd 

 without corroboration. Gnathopods 1 and 2 very setose according to flgure, 

 5^'^ Joint triangulär, umch shorter than 6*^, 6*^'^ longer than broad, widest 

 at the somewhat oblique palm, which is well defined by a strong spine at 

 the angle. Gnathopod 2 rather larger than gnathopod 1. Peraeopods 1 

 and 2 slender, equal, shorter than the 3 following. which successively encrease 

 in length, with oval 2^ Joint. Uropods 1 and 2 short. each with equal rami. 

 Uropod 3, inner ramus in 6 ^i\^, in Q 7? as long as outer, tipped with 2 spinules 

 and a seta, outer ramus with l^*joint in ö thrice as long as peduncle and subequal 

 to 2*1 Joint, in 9 twice as long as peduncle and twice as long as 2'^ Joint. Telson 

 cleft beyond the middle, apices subacute. Colour snow-white. L. 10— 14 mm. 



Oaves of Adelsberg and Lueg in Krain. 



5. N. puteanus (C.L.Koch) 1835 Gammarus p. (part.: forma I), O.L.Koch, 

 ('. M. A., v.o nr.2 1862 Niphargus p., Bäte, Oat. Amphip. ßrit. Mus., p. 177 t. 32 f. 4 | 

 1890 N. ratisbonensis, Wrzeäniowski in: Z. wiss. Zool.. ».50 p. 662, 673, 696. 



Scarcely distinguishable from N. stygius, except in having yellow eyes, 

 gnathopods 1 and 2, 6*^' Joint very large, almost rectangular, broader than 

 long, and the otherwise pellucid body streaked along the edges of the peraeon 

 Segments and to the and of pleon with a yellow ochre stripe. L. 12*5 mm. 



ßegensburg, in wells; also at Poitiers. 



