390 Eucrangonyx 



Eye.s small, round, without dark pigment. Anteniia 1, P* Joint little longer 

 than 2^, 3*^ % ^^ ^^^S ^^ 2^' flagellum not twice as long as pedimcle, with 

 14 joints, accossory flagellum not longer than 1^* Joint of piimary. Antenna 2, 

 ultimate and peuultimate joints of peduncle (^qual. Hagellum of few joints. 

 (jnathopod 1 (in a 9 5 mm long), 5*'» Joint trapezoidal, 6*'' oblong, palm 

 little oblique, much shorter than bind margin; gnathopod 2 similar, but 

 6*^ Joint longer, with more oblique palm. In largest 9 gnathopod 1 has a 

 more triangulär 5*^^ Joint and the G*^' more expanded, wider than the 5^^, 

 and gnathopod 2 also has the palm much more oblique and longer than 

 hind margin. Peraeopods 1—5 differ from those in E. gracilis in having the 

 spines more uumerous, longer and more sleuder. Uropods 1 and 2 have 

 the spines shorter and more obtuse than they usually are in E. gracilis, but 

 otherwise these 2 closely allied species agree in uropods and telson. L. reaching 

 7-5 mm. 



Indiana (wells iu Orleans and at New Albany). 



4. E. gracilis (S. 1. Sm.) 1871 Crangonyx y., S. I. Smith (& A. K. Verrill) in: 

 Ainer. J. Sei., ser. 3 v.2 p. 453 | 1893 C. g., A. Della Valle in : F. Fl. Neapel, v. 20 p. 682 j 

 1894 O.g., Chilton in: Tr. Linn. Soc. London, ser. 2 v.d j). 218 | 1899 Eucranyonyx y., 

 T. Stebbing in: Tr. Linn. Soc. London, ser. 2 v.l p. 423. 



Pleon Segments 1 — 3, postero-lateral Corners produced and ending iu a small 

 tooth. Eyes slightly elougated, composed of a few black facets. Antenna 

 1 rather more than half as long as body, 1*** and 2<^ joints subequal, 3<3 -/s ^^ ^^^^ 

 as 2^ flagellum not twice as long as peduncle, with about 20 joints, accessory 

 flagellum as long as 1^* Joint of primary. Antenna 2 al)out half as long as 

 antenna 1, ultimate and penultimate joints of peduncle long. sul)equal, flagellum 

 rather shorter than peduncle, 7- or 8-jointed. Gnathopods 1 and 2 of 9 as in 

 E. packardii (p. 389). In d gnathopod 1 has palm slightly oblique, strongly 

 spined, gnathopod 2 has 6*i> Joint proportionally slioi'ter than in 9 , encreasing 

 considerably iu breadth distally. palm much more oblique, slightly arcuate 

 and spinöse. Peraeopod 5 slightly longer than peraeopods 8 and 4, 2"* Joint in all 

 luiving hind margin serrate. üropod 3 j*eaching apex of uropod 2, outer ramus 

 nearly twice as loug as peduncle. armed witli a few sleuder spines, inner 

 minute, unarmed, shorter than diameter of outer. Telson scarcely as long as 

 peduncle of uropod 3, a little broader than loug, apical margin with a ti-ian- 

 gular emargination, ou either side of which the extremity is truncate, and armed 

 with three spines. L. o 6—7, ö ^ — 14 mm. 



North-America (Lake Superior, Lake Huron). 



5. .E. antennatus (Pack.) 1881 Gnmyonyx «., Packard in: Ainer. Natural., 

 (-.15 p.880 I 1888C.a., Packard in: 31em. Ac. Washington, 'ü.4I p.36 t.5 f. 12, 14: tcxtF. | 

 1893 Ca., A. Della Valle in: F. Fl. Neapel, <). 20 p. 682 | 1899 Eucrangonyx a., T. 

 Stebbing in: Tr. Linn. Soc. London, ser. 2 v.l p. 423. 



Side-plates 1 — 4 very unequal, 1^* very small, 4* uuusually large and 

 nearly Square, but seeraiugly much excavate behind. Pleon segments 1 — 3, 

 postero-lateral corners subacute. Eyes distinct, well developed, black, but 

 not so distinct and only ^4 '^^ large as in E. gracilis. Antenna 1 nearly 

 -/ä as long as the body, 2^ Joint of peduncle is said to be much longer 

 than in E. gracilis, 3^ rather more than half 2^, flagellum 20— 24-jointed. 

 Antenna 2 (infigure) not ^g as long as antenna 1. Gnathopods 1 and 2 and pei'aeo- 

 pods 1 — 5 apparently as in E. gracilis, as also uropods 1^ — 3 and telson, but 

 rami of uropods are said to be slightly stontei- nnd more polished, and the 

 spinules a little stouter. Colom- purplish. L. 6 — 7 mm. 



Tennessee (subterrauean stream of Nickajack Oave). 



