COPEPODA 



137 



fo*. Size of specimen from Thor St. 90 4-92 mm.; anterior division 3-59 mm.; nrosome 1-33. 



The head is, as in the female, mounted with a distinct frontal keel; the body is more slender 

 than that of the female and even more so than that of the preceding species. The lateral corners are 

 regularly rounded. The St. 2 of the caudal ramus is longer than the urosome. The antennulac 

 extend about to the middle of the abdomen. The mouth-limbs are like those of the preceding 

 species, but soft-skinned, short rounded appendages were observed in the Ei I — II of the max- 

 illulae, and the appendages of the maxillae are better developed. The pes I shows the same 

 difference as in U. minor, and the second basipodite of the fourth pair of legs is smooth. 



The fifth pair of legs differs from that of U. minor by a few features only ; the Text-fig. 36. 

 inner margin of the Ri dext. (fig. 2 c) has basally a distinct tooth, followed by a lamina Undeuchtzte 



major Giesbr. 



with a distinct process in the middle, in shape different from that of the preceding species; ftf. PesVsin. 

 the outer margin of Re I dext. has a rather low keel, but no distinct teeth. The Re III 

 sin. (fig. 2 d) differs by shorter terminal seta and by the different arrangement of the setae. The left 

 endopodite is more slender (text-fig. 36). 



Y°. (St. V). Size of female from Thor St. 82 4-95 mm. ; anterior division 3-91 mm.; urosome 1-04 mm. 



The shape of body with the frontal keel is scarcely different from that of the adult female. 



The Se Re II in the first pair of legs is not shorter than in the female; the inner margin of 

 the second basipodite in the fourth pair of legs is completely smooth. 



Occurrence. The S/S Thor has gathered this species at three stations only: 



'5/6 1905 St. 82 5i°oo E. N. n°43 U W. Yt. 1200 M. Wire 1 f? (with sperm.), 2 y? (V). 

 2 % 1905 St. 88 48^9 E. N. 8°30 E. W. Yt. 300 M. Wire 55 f? (13 with sp.). 

 2I / 6 1905 St. 90 47°47 Iv. N. 8°oo E. W. Yt. 300 M. Wire 25 f? (5 with sp.), 5 fb*. 



Distribution. This species was recorded by Farran "on every station of from 350 to 1000 

 fathoms and in 16 out of 34 gatherings, generally in moderate numbers" on the west coast of Ireland 

 as far north as 54 E. N. It has been met with during the Prince of Monaco's cruises in the East 

 Atlantic and was recorded as rather numerous at several stations in the South Atlantic even south 

 of Africa at about 40 E. S. 35 Iv. E. by the Gauss Expedition. 



It has been recorded by Esterly from the Gulf of California, by Giesbrecht from the 

 Pacific (E.N. 20 E. E. 173) and by Scott from the Malay Archipelago. 



Remarks. In spite of the few differences enumerated above, I do not doubt that my Atlantic 

 specimens are identical with Giesbrecht's from the Pacific. 



A. Scott is certainly right in determining the male referred by Esterly to this species as a 

 species of Euchcete, as well as in regarding the male of Thompson's Scolecithrix cristata as belonging 

 to this species. 



39. Undeuchaete superba n. sp. 



(PI. IV figs 6 a— b; PI. V figs 1 a— c; text-figs 37 a— f.) 

 Description. f<j>. Size of specimen from Thor St. 183 was 642 mm.; anterior division 5-11 mm.; 



urosome 1-31 mm. 



A rounded, rather low, but fairly prominent frontal keel is found; the undivided rostrum is short, 



but strong (text-fig. 37 a). The head and the first tergite are fairly well separated ; the fourth and fifth 



t8 

 The Ingolf-Expedition, III. 4. 



