exopod is 8-segmented, and the endopod 2-seg- 

 mented. The first segment of the endopod is 

 about 2.5 times as long as the second. 



The mandibular palp (fig. 11) is slender and 

 lacks setae on the basis. The endopod is slightly 

 longer than the exopod. The cutting edge (fig. 

 12) of the mandibular blade consists of 2 

 strong rostral teeth, the inner of which has 2 

 small acute teeth along the internal margin 

 and another along the external margin. 



In the maxillule (fig. 13), the first inner lobe 

 and the exopod are elongate. The first inner 

 lobe has distally 7 spiniform setae, 2 of which 

 are notably strong. The second and third inner 

 lobes are small, and have 1 and 3 setae, 

 respectively. 



The maxilla (fig. 14) bears 6 well-developed 

 lobes. The first lobe has 3 setae, each of the 

 second to fourth lobes 2 setae, the fifth lobe 1 

 seta plus 1 strong spine, and the sixth lobe 

 2 setae plus 1 strong spine. The spine of the 

 sixth lobe is slightly smaller than that of the 

 fifth lobe. The endopod is 3-segmented and has 

 7 setae. 



The coxa of the maxilliped (fig. 15) has 3 

 lobes, which have 2, 3, and 3 setae, respectively. 

 The basis has 2 lobes, each with 2 setae. The 

 endopod is 5-segmented; the first and second 

 segments each have 4 setae, the third and 

 fourth have 3, and the fifth has 4. 



The basipod of the first leg (fig. 16) has 1 

 internal seta on the coxa and 1 external seta on 

 the basis. Both the exopod and the endopod are 

 3-segmented. The first and second exopodal seg- 

 ments each have 1 internal seta and 1 external 

 spine. The external spine of the first segment 

 is notably long, extending beyond the end of the 

 spine on the second segment. The third exopodal 

 segment has 2 external spines, 4 internal setae, 

 and 1 terminal spine. The endopod is about as 

 long as the first 2 exopodal segments combined 

 and has 1 seta on the first segment, 2 on the 

 second, and 5 on the third. 



The second to fourth pairs of legs (figs. 17- 

 19) are similar. The coxa has 1 internal seta. 

 The basis is naked in the second and third legs 

 but has an external seta in the fourth leg. The 

 exopod is 3-segmented; the first and second 

 segments each have 1 external spine and 1 in- 

 ternal seta; and the third segment has 3 exter- 

 nal spines, 5 internal setae, and 1 terminal 



spine. The endopod is also 3-segmented. The 

 first segment bears 1 seta, and the second seg- 

 ment 2 setae. The third segments of the second 

 and fourth legs have 7 setae, but that of the 

 third leg has 8 setae. 



The fifth pair of legs (fig. 20) is asymmetri- 

 cal. The coxa of the left leg has a strong tooth 

 on the internal margin. The basis in both the 

 right and the left legs has a long plumose 

 external seta. The second exopodal segment of 

 the right leg has a large, conical protrusion on 

 the internal margin. The right and left third 

 exopodal segments both have 2 external spines 

 and 1 large terminal spine ; the first external 

 spine of the right third exopodal segment is 

 spinose and as long as the terminal spine. The 

 endopods of both legs are 3-segmented ; the 

 first segment lacks setae, but the second and 

 third segments have 1 seta and 6 setae, 

 respectively. 



Remarks 



The present specimens are in full agreement 

 with the description by Giesbrecht (1892) ex- 

 cept for the urosome, which seems to be some- 

 what shorter than that figured by him. This 

 difference may be due to the telescoping of the 

 segments. The female is not known. 



Haloptilus spiniceps (Giesbrecht, 1892) 



Occurrence 



Sta. 3. 6 adult females, 4.41 to 4.80 mm. 

 Sta. 5. 5 adult females, 4.12 to 4.99 mm. 

 Sta. 7. 2 adult females, 4.50 to 4.60 mm. 



Remarks 



This species can readily be distinguished 

 from the other species of the genus by the 

 short, hooked, spiniform projection of the fore- 

 head, viewed from the side. 



Augaptilns spinifrons Sars, 1907 

 (Plate 12, figs. 1-5) 



Occurrence 



Sta. 5. 1 adult female, 3.55 mm. 

 Remarks 



The female of this species can be Identified 

 by five characters: The anterior end of the 

 body is produced into an acute spiniform proc- 

 ess that is pointed downward (figs. 1 and 2) — 



CALANOID COPEPODS FROM NORTH PACIFIC 



563 



