NO. 3 HARTMAN : ORBINIIDAE, APISTOBRANCHIDAE, PARAONIDAE 299 



Naineris dendritica (Kinberg) 1867 

 Plate 36, figs. 1-3; plate 37, figs. 1-7 



Anthostoma dendriticum Kinberg, 1867, p. 337. 



Naineris robusta and Naineris longa Moore, 1909, pp. 262-267, pi. 8, 



figs. 34-42. 

 Nainereis hespera Chamberlin, 1919b, pp. 14-15. 

 Nainereis laevigata Berkeley and Berkeley, 1941, p. 41 ; Berkeley and 



Berkeley, 1942, p. 196; Hartman, 1944c, p. 257. 

 Naineris dendritica Hartman, 1948b, pp. 102-103. 



Collections.— 901-38 (1), 1204-40 (1), 1222-41 (12), 1228-41 

 (1), 1315-41 (1), 1370-41 (1), 1437-41 (6), 1443-41 (many), 1445- 

 42 (1), 1446-42 (1), 1447-42 (1), 1449-42 (1), 1457-42 (4), 1459- 

 42 (10), 1464-42 (3), 1468-42 (18), 1472-42 (1), 1474-42 (1), 

 1477-42 (3), 1487-42 (1), 1488-42 (5), 1490-42 (many), 1491-42 

 (10), 1492-42 (4), 1501-42 (1), also many others from the north- 

 eastern Pacific Ocean from Alaska south to southern California, chiefly 

 from intertidal low littoral zones. 



The prostomium is broadly rounded in front. The everted proboscis 

 is much branched and extensive. Branchiae are first present from about 

 segment 12 or rarely as early as 7 or not before segment 14 or 15; the 

 first few pairs are small and they gradually increase in size so that by 

 about segment 30 they meet across the middorsum or stand erect (pi. 

 36, fig. 2) ; they are simple and lightly fimbriated along their lateral 

 margins. 



Transition from thorax to abdomen is at about segment 20 or not 

 before 30. Thoracic notopodial postsetal lobes are long and triangular; 

 the corresponding neuropodial lobes are fleshy ridges in which the 

 superiormost edge is slightly enlarged so as to resemble a small papilla 

 (pi. 36, figs. 1, 2). This is in contrast with N. laevigata (see above) in 

 which this lobe is more or less foliaceous and prolonged at its upper 

 edge. Thoracic neuropodia at maximum development have two or more 

 anterior rows of pointed setae; the anteriormost (pi. 37, fig. 7) are 

 sharply bent and conspicuously denticulated along the cutting edge; 

 those farther back (pi. 37, fig. 6) are transitional between the anterior- 

 most and the subuluncini (pi. 37, fig. 5) which occur in the uppermost 

 part of the fascicle. The posteriormost row has uncini in which the 

 cutting edge is smooth (pi. 37, fig. 3) or transversely ridged (pi. 37, fig. 

 4), especially for those in the inferiormost position. 



