a row of short setae at the anterior margin of the dorsodistal indentation, 



2 of them thicker and longer (primary setae?); minute covering chetae, 

 which are pointed or blunt, and thin, small, and several short, yellowish 

 spinelike setae at the anterior margin; short setae and 1 or 2 thicker and 

 longer setae at the posterior margin of the distal indentation, except in its 

 basal third; further basally, near the margin of the indentation, stands the 

 posterior, primary seta, which is dark brown and long on midleg and fore- 

 leg, and short on the hind legs. Anterior surface of coxa with thin, small, 

 covering chetae; a few larger, brownish setae among them on the sub- 

 dorsal side; covering chetae larger on the posterior surface; interspersed 

 with several small, branched, thick setae in the distal part of the midlegs; 

 ventral side with only small, sparse covering setae; both distoventral setae 

 long; anterior seta slightly longer than posterior seta; short, light setae 

 among them and laterally. 



487 Anterior and posterior surface of trochanter, including apical part of basal 

 segment, with small spinelike setae which are more numerous and massive 

 posteriorly; they are small on the basal segment; posterior, primary seta 

 situated subdorsally, well marked; ventral side with covering chetae; they 

 are slightly larger on the 1 st segment, long, transparent, setuliform, with a 

 thick base on the 2nd segment; several thicker, brownish, long setae among 

 them. 



Dorsal surface of femur uniformly convex; ventral margin almost straight; 

 dorsal side with short, light setae including the primary, basodorsal seta, 

 the distodorsal seta, which is longer than the others, and displaced to the 

 posterior margin; a row of small, light, spinelike setae anteriorly; isolated, 

 small setae more dorsally; primary anterior seta spinelike, situated sub- 

 ventrally near the apex; setae of posterior surface numerous, mainly sub- 

 ventrally; primary posterior seta situated distally, relatively long; anterior 

 side with a row of short, thick, divided spinelike setae; a few long setae and 

 several dark brown, thicker setae (including 2 primary setae) posteriorly. 



Tibia of midleg and hind legs slightly longer than tarsus; thin light setae 

 dorsally; a long, yellowish seta distally and dorsally; small setae anteriorly 

 and posteriorly; primary posterior seta situated subventrally, brown,- long, 

 I a. as long as the tarsus; ventral side with a row of strong, small spines 

 which are longer apically; hind legs with 4 -branched setae anterior to them; 



3 similar setae situated subventrally, near the apex. 



Tarsus with similar light setae as on the tibia, and with a strong, relatively 

 long, dark brown distodorsal seta; anterior and posterior surface with 

 sparse, small setae; a row of spinules ventrally; posterior surface of mid- 

 legs with 2 massive spines; posterior surface of hind legs with 3 massive 

 spines. 



Claw dark, curved; basal seta forming a short, massive, blunt spine. 



Abdomen uniformly broad on the first 5 segments, tapering on the 

 3 following segments; dorsal surface of segment 8 more developed than 

 ventral surface; segment 9 very narrow. Ventral gills present on 

 segments 1—7; pleural gills present on segments 3—7; ventral outer gills 

 with 2 branches; median gills with 1 branch; stalks of gills indistinctly 

 2 -segmented or 3 -segmented. 



Stalk of pleural gills modified into a short, muscular, flattened appendage 

 which acts as organ of movement, ensuring a current in the chambers 

 inhabited by the larvae; number of gill filaments 1 or 2, or filaments absent 

 at the apex. 



555 



