COPEPODA 



105 



surface of Li i, but has about 14 fairly stroug spinules on the anterior surface of Li III. The third 

 basipodite of the maxiUipeds is i-i as long as the two first ones and 28 as long as the Ri; the exterior 

 margin of the second basipodite bears a fairly slender rounded lamella (text-fig. 26 d) and the fourth 

 lobe is divided most distinctly by a deep cleft into a posterior • '' 



smooth division and an anterior one, which possesses 3 setae 

 in addition to the sensory lobe. 



The Re I— II of the first pair of legs are completely 

 fused with the exception of a small lateral incision. The ter- 

 minal seta of the second pair of legs has 19 teeth, and is dis- 

 tinctly longer than the Re III. The second basipodite of the 

 fourth pair of legs has 20 lamellous bristles. The secre- 

 tory pore of Re I is wanting in pes II, present in III — IV. 



The labritm is anteriorly scarcely different from that 

 of the preceding species; orally it is as seen in fig. 6 a in main 

 features like G. ICntfipi (V\. Ill fig. 2e); the longitudinal series has 

 in most groups two or more rows of hairs. The transverse groups 

 of short hairs around the median circular spot Nr. 4 are on each 

 side dissolved into a somewhat triangular group as seen in fig. 

 6 a, and somewhat behind it a transverse area of short spines 

 or granules is found. 



The laiiiiiia lahmlis is like that of fig. 5 e but is almost 

 smooth; in front of this we have the usual two lateral series 

 of slender spines, of which the more lateral is almost semi- 

 circular, while the median one is very short. In front, by a smooth 

 area separated from the lamina, a wide area covered with flat 

 granules and almost fused with the corresponding part of the 

 other side is found. The 4 transverse groups of densely placed 

 short spines behind the lamina are like those of G. Kncppt {i\g. 3 c). 

 The lateral longitudinal series shows the following structure: 

 Sen N r. I consists of 10 short hairs in a transverse group and 

 of 30 in a longitudinal group, continued upon the lobus labialis 

 and partly confluent with the series Nr. 2, which has 20 slender hairs placed longitudinally. The 

 series Nr. 3 has two groups behind, of which the more lateral is more posterior (in contrast to fig. jf 

 PI. II), and a longitudinal row which on the posterior surface of the lobus labialis is continued to 

 near the tip. The series Nr. 4 is posteriorly placed almost transversely, forming a convexity, turning 

 backwards and almost reaching corresponding part of opposite side, and is anteriorly continued to tip 

 of the lobus labialis. The series Nr. 5 consists of a median transverse group of about 30 longer and 

 shorter setae placed near the middle, and a more lateral partly longitudinal group; this group is 

 not continued directly into any series on the labial lobe, but probably corresponds to the most medial 

 one which is dissolved into independent groups. Possibly the series 5 corresponds also to the longitu- 



The Ingolf-Expedition. III. 4. ^ 





Text-fig. 26. Gactanus pileatus Farr. 



a. f9. Head X i8. 



b. f9. Right caudal ramus in abnormal spec- 



imen X .57. 



c. f9. Maxillipes sin in anterior view X 57- 



d. y d" (Stage V) m. s. in ant. view X 57- 



e. y c? (Stage V) pes V in anterior view X 57- 



