COPEPODA 



107 



Distribution. About this species Far ran writes (1908 p. 36) "this species is a very noticeable 

 feature in the deep-water fauna off the west coast of Ireland, occurring often in considerable numbers, 

 in almost every tow-net from 200 to 1150 fathoms". 



The gatherings of the Thor seem to show that it is much more abundant south of 60° L. N. 

 even if it is found in Denmark Strait as far north as 65° L,. N. By Wolfenden it has been 

 recorded from the South Atlantic, and it was found by the Monaco Expedition, as well as at 5 stations 

 from the deep water of the Malay Achipelago (5 females only). 



Remarks. Though I have not seen Farran's original description, I am quite sure that my 

 species is identical with his G.pilcatus and different from Canu's G. caudani (if this author has not 

 examined an abnormal specimen). As I have examined specimens determined by Sars as G. caudani^ 

 no doubts exist 'about its identification with the Monaco's species; and the same is the case with 

 Wolf end en's species, from the South Atlantic. As the lamina of the maxillipeds (PI. VIII fig. 13) 

 was differently shaped in the Siboga specimens (length 57 mm.), I am not quite convinced of Scott's 

 identification. Scott regards Esterly's G. unicoruis as identical with his G. caudani, which he 

 regards as the synonym of G. pilcafns, but he is scarcely right, as the lamina of the maxillipeds 

 has quite another shape in Esterly's species (1906 PI. XII fig. 54). 



28. Gaetanus miles Giesbrecht. 

 (PI. Ill figs 7 a— b). 



1 888. Gaetanus miles n. sp. Giesbrecht, p. 335. 



1893, — — Giesbr. Giesbrecht, p. 219, taf. 14 & 36. 



1895. — — — Giesbrecht, p. 248. 



1898. — — — Giesbrecht & vSchmeil, p. 32. 



1903. — — — Norman, p. 136. 



1903. — — — J. C. Thomsen, p. 17. 



1904. — — — Cleve, p. 191. 



1905. Gaetanus miles Giesbr. G. O. Sars, p. 3. 



igo6. — — — Pearson, p. 14. 



190S. — — — Farran, p. 36. 



1908. --- — — V. Bremen, p. 39, fig. 42. 



1909. — — — A.Scott, pp.44— 45, pi. Vlll figs 



1—8 



1913. — — — Wolfenden, p. 231. 



Description, f $. Size of specimen from Thor St. 82 was 4-21 mm.; anterior division 3-4, urosome 

 o-8i mm. Giesbrecht's specimen measured 3-5, Scott's 4-3 and Wolfenden's 3 mm. 



The shape of the body is scarcely different from Giesbrecht's figure; the anterior division 

 is 4-2 as long as the urosome, which has the relative length of the somites and furcal rami as 

 follows: 34, 13, II, II, 15; the furcal rami are 1-3 as long as wide. The anienmtiac diiier irom those of 

 Giesbrecht's specimen by the proportional length of the segments; the segment 19 is a Httle longer 

 than 22, which is the longest according to Giesbrecht, and this again is a Httle longer than 

 20; the segments So^c), 13 and 24^25 are in G. miles of almost equal length, but in my specimens 

 segment 13 is i-i as long as 8 cn; 9 and i-2 as long as 24 0= 25. The mouth-appendages, with the excep- 

 tion of the maxillipeds, are scarcely different from those of G. miles; in this pair of appendages the 

 third basipodite is 3 times as long as the endopodite, and i'3 as long as the Basp. I— II; the plate- 

 shaped process of the exterior surface of the second basipodite is rounded and almost semicircular 

 (fig. 7a), and distinctly different from Giesbrecht's fig. 24. Taf 14. In the first pair of legs the 

 articular line between Re I — II was scarcely indicated; the Ri of the second pair of legs has the 

 articulation between Ri I— II fairly distinct anteriorly, and scarcely indicated posteriorly; the second basi- 



14* 



