Eurystheus 611 



Synopsis of species: 

 f Eyes lageniform or oblong — 2. 





\ Eyes not lageniform or oblong — 3. 

 Eyes lageniform 1. E. atlanticus . . p. 611 



Eyes oblong 2. E. afer p. 612 



Pleon segment 4 dorsally dentate — 4. 

 Pleon segment 4 not dorsally dentate — 7. 



, Telson emarginate 3. E. thompsonl . . p. 612 



\ Telson not emarginate — 5. 



{ 



. Pleon segment 4 with 1 medio-dorsal tooth — - 6. 



\ Pleon segment 4 with 3 medio-dorsal teeth . . 4. E. erassipes . . p. 612 



j Gnathopod 2 in $ , paün without defining tooth . 5. E. thomsoni . . p. 613 

 \ Gnathopod 2 in $ , pahn with defining teeth . . 6. E. ostroumo-wri . p. 614 



( Gnathopod 2 in (5, 2d Joint greatly expanded . . 7. E. exsertipes . . p. 614 

 \ Gnathopod 2 in cj, 2d Joint not greatly expanded — 8. 



ILimbs of peraeon thickly coated with setae and 

 fine hairs 8. E. hirsutus . . . p. 615 

 Limbs of peraeon not thickly coated with setae 

 and fine hairs — 0. 

 {Side-plate 3 in <? subacutely produced forward . 9. E. dentifer . . . p. 615 

 Side-plate 3 in cj not subacutely produced for- 

 ward — 10. 



(Gnathopod 2 in cJ, finger closing on to the sur- 

 face of 6th. joint — 11. 

 Gnathopod 2 in ^, finger closing on to the margin 

 of 6th Joint — 12. 

 j Gnathopod 2 in (5, 6th Joint narrow, finger short . 10. E. longimanus . p. 616 

 \ Gnathopod 2 in (J, 6th joint broad, finger long . 11. E. palmatus . . . p. 616 



j Telson apically emarginate 12. E. chiltoni . . . p. 617 



\ Telson not emarginate . . " 13. E. maculatus . . p. 617 



1. E. atlanticus (Stebb.) 1888 Gammaropsis atlantica, T. Stebbing in: Rep. 

 Voy. Challenger, v. 29 p. 1101 t. 114 | 1893 Protomedeia? a., A. DellaValle in: F.Fl. 

 Neapel. u20 p. 441. 



9 . Head, lateral lobes narrow, acute, strongly produced. Side-plate 1 

 rather produced forward, but obtusely; 2^ broader than deep. Pleon segment 3, 

 postero-lateral corners rounded. Eyes lageniform, close to margin of head, 

 the narrow neck uppermost. -Antenna 1, 3*^ joint subequal to 1^*, shorter than 

 2*^; flagellum 17-jointed, accessory flagellum 6-jointed. Antenna 2, ante- 

 penultimate Joint of peduncle a little concave above as if to receive lateral 

 lobe of head; ultimate and penultimate joints subequalj flagellum 10-jointed. 

 Gnathopod 1, 5*^ joint rather shorter and narrower than 6*^; G*'^ oblong 

 oval, palm oblique, slightly defined, longer than bind margin, slightly over- 

 lapped by the finger. Gnathopod 2 much largör; 5*^ Joint much shorter than 

 6*^ cup-shaped; 6*^ oblong, palm slightly oblique, in-egularly convex, crenate, 

 defined by a tooth, which is overlapped by apex of seiTulate finger. Peraeo- 

 pods 3 — 5, 2^ Joint well expanded, narrowing distally; finger short. Uropod 3, 

 peduncle a little longer than the rami. Telson a little longer than broad, 

 with triangulär apex, a plumose setule at the angles of its base and a spine 

 on the surface near each angle. Colour, dark stellate markings over much 

 of the surface, including the mouth-parts. L. 7 mm. — 6 unknown. 



Tropical Atlantic (St. Vincent [Cape Verde Islands]). 



89* 



