328 Atylidae, Atylus 



Lower lip with inDer lobes obsolescent. Mandible (Fig. 77 p. 333) with palp. 

 Maxiila 1 (Fig. 78 p. 333), inner plate with several setae. Maxiila 2, inner plate 

 partially fringed on inner margin. Maxillipeds, palp well developed. Gnatho- 

 pods 1 and 2 siibchelate, gnathopod 2 generally the raore slender. Peraeo- 

 pods 1 — 5, liuger iisiially pointing backward. Uropod 3, rami subequal, 

 extending beyond those of uropod 2. Telson short, deeply cleft. 



Marine. 



2 genera, 8 accepted species and 1 obscure. 



Synopsis o£ genera: 



Mandibular palp strong; pleon segment 4 not dorsally 



notched 1. Gen. Atylus . . . p. B28 



Mandibular palp sligM (Fig. 77 p. 333); pleon segment 4 



dorsally notched 2. Gen. Nototropis . p. 320 



1. Gen. Atylus Leach 



1815 Atylus (Sp. un.: Ä. carinatiis), Leach, Zool. Mise, v.2 p. 21 j 1815 A., 

 Leach in: Tr. Linn. Sog. London, «.11 p. 357 | 1888 A., T. Stebbing in: Rep. Voy. 

 Challenger, «. 29 p. 907 | 1893 A., G. 0. Sars, Crust. Norway, v. 1 p.471 | 1893 A. (part.")r 

 A. DellaValle in: F. Fl. Neapel, f. 20 p. 697. 



Body strongly compressed, carinate. Pleon segment 4 dorsally produced^ 

 but without antecedent notch. Side-plates not deep. Antennae 1 and 2 

 subequal, not very slender, accessory flagellum rudimentary. Mandible 

 normal, palp large, 3*^ Joint long and spinöse. Maxiila 2, outer plate wider 

 and longer than inner. Maxillipeds rather large, outer plates not reaching 

 end of palp's 2"^^ Joint, palp rather strong. Gnathopods 1 and 2 short but 

 strong, with broad 6^^^ Joint. Peraeopods 1—5 rather short, peraeopod 5 

 with 2'^ Joint much dilated, finger reversed. Branchial vesicles simple. 

 Uropod 3, rami long, nearly equal, not reaching beyond uropod 1. Telsou 

 deeply cleft. 



1 species. 



1. A. carinatus (F.) 1793 Gammarusc, J. C. Fabricius, Ent. syst., v.2 p.515 | 

 1815 Atylus c, Leach, Zool. Mise, v.2 p. 22 t. 69 | 1874 A. c, ßnchhofz in: Zweite U. 

 Nordpolarf., v. 2 p. 357 Crust. t. 10 | 1876 A. c, A. Boeck, Skand. Arkt. Amphip., v. 2 

 p. 324 I 1893 A. c, G. O. Sars, Crust. Norway, v. 1 p. 471 t. 166 f. 1 | 1893 A. c, A. Della 

 Valle in: F. Fl. Neapel, v.20 p. 701 t. 60 f. 3 | 1838 AmphitJioe carinata, Xröyer in: 

 Danske Selsk. Afh., v.l p. 256 t. 2 f. 6 a— kj 1838 A.c., Kröyer in: Naturh. Tidsskr., 

 v.2 p. 259 I 1866 ParamphWioe c, Goes in: Öfv. Ak. Förh., t;. 22 p. 523. 



Body elongate, carinate throughout, the keel produced into a tooth in 

 peraeon segment 7 and pleon segments 1 — 4. Head, rostrum rather large^ 

 compressed, distally somewhat expanded, ending obtusely; lateral corners 

 subtruucate. Side-plates 1 — 4 almost quadrangular, 4**^ broader, scarcely 

 deeper than the preceding, little emarginate, 5*^ with front lobe the deeper. 

 Pleon segment 3, postero-lateral corners subquadrate. Eyes very small, 

 rounded oval, prominent, very dark. Antenna 1 not nearly Vs '^s long as 

 body, 1^^ Joint as long as 2^, 3'^ about half 2*^, flagellum scarcely louger 

 than peduncle, 22-jointed, accessory flagellum 1-jointed. very small. Antenna 2 

 not (Boeck: a little) longer, ultimate and penultimate joints of peduucle sub- 

 equal, together longer than the 20-jointed flagellum. Gnathopod 1, 5*^ Joint 

 not very long, but nearly as long as 6*^, 6*^ rounded oval, front margin 

 densely setose, palm shorter than bind margin, with which it forms an 



