204 



COPEPODS OF LAST CRUISE OF CARNEGIE 



turnal, the others diurnal. This, then, is a fifth species which 

 remains at the surface during the day and night and does 

 not descend to lower depths. All the Siboga specimens were 

 taken in surface tows with the exception of 2 specimens 

 which were captured in a vertical haul. 



Pontella tenuiremis CJieshrecht 

 (Figures 93, 97) 

 [PontcUa tenuiremis Giesbrecht, Atti R. Accad. Lincei, Rome, 

 ser. 4, vol. 5, sem. 2, p. 28, 1S89; Fauna und Flora des Golfes 

 von Neapel, vol. ig, pp. 462, 477, pi. 24, figs. 24-26; pi. 40, 

 figs- 3. 4> 7. 37. iSg^-] 

 Not present in the Atlantic plankton, but well distributed 

 in the southeastern and central Pacific. It was taken in 5 

 nocturnal and 27 diurnal surface tows, i 50-meter tow, and 

 I loo-meter tow. It is evidently positive to ordinary light but 

 may become negative to strong light. The genital segment 

 has a flattened genital swelling and a small process on the 

 right side behind it. 



Genus PONTELLINA (Dana), 1853 

 Pontellina plumata ( Dana ) 



(Figure 100) 



\Poiitcllii plmnatii Dana, Proc. Amer. Acad. Arts and Sci., vol. 



2, p. 27, 1849.] 

 [Pontellina plumata Dana, U. S. Exploring Exped., 1838-1842 



(Wilkes), vol. 14, pt. 2, Crustacea, pp. 1135, 1136, 1853; pi. 



79, fig. loa-d, 1855.] 



Well distributed in both oceans, except in the northern 

 regions and in the southern part of the Pacific. It was taken 

 in 8 nocturnal and 33 diurnal surface tows, 37 50-meter 

 tows, and 28 100-meter tows. It is thus almost indifferent to 

 light, but slightly favors the two upper tows. It is very 

 generally distributed in the warm regions of all oceans, but 

 rarely occurs in abundance anywhere. Thirty-four of the 

 present abundance records were solitary specimens and 

 twenty-five others were expressed in numerals. 



Genus PONTELLOPSIS Brady, 1883 

 Pontellopsis armata (C}iesbrecht) 



\Monops armutiis Giesbrecht, Atti R. Accad. Lincei, Rome, 

 ser. 4, vol. 5, sem. 2, p. 28, i88g; Fauna und Flora des Golfes 

 von Neapel, vol. 19, pp. 487, 496, pi. 26, figs. 19, 26, 27; pi. 

 4T, figs. 46, 47, 58, 1892.] 



Two females of this species were obtained in the surface 

 tow at station 98, and this is the only record for the cruise. 

 This species was reported by A. Scott (1909, p. 170) as "the 

 most abundant member of the genus" in the Siboga plank- 

 ton. It is worthy of note that, with one exception, the Siboga 

 specimens were obtained at the surface. It seems reasonable, 

 therefore, to record the species as positive to light. 



Pontellopsis lubbockii (Ciicsbrecht) 



[Moiiops liihbocl{ii Giesbrecht, Atti R. Accad. Lincei, Rome, 

 ser. 4, vol. 5, sem. 2, p. 29, 18S9; Fauna und Flora des Golfes 

 von Neapel, vol. 19, pp. 487, 496, pi. 26, figs. 18, 32; pi. 41, 

 figs. 60, 63, 68, 1892.] 



About a dozen specimens, including i male and 2 adult 

 females and the remainder development stages, were taken at 

 the surface at station 40. This is the only record for the cruise, 

 but the species has been reported before from the tropical 

 Pacific. The long process, enlarged at the tip, at the right 

 posterior corner of the last thoracic segment in the male is a 

 distinguishing character. 



Pontellopsis perspicax (Dana) 



(Figure 99) 



[Pontella perspicax Dana, Proc. Amer. .*\cad. Arts and Sci., 



vol. 2, p. 32, 1849.] 

 [Pontellina perspicax Dana, U. S. Exploring Exped., 1838-1842 



(Wilkes), vol. 14, pt. 2, Crustacea, p. 1155, 1853; P'- 81, fig. 



2a-d, 1855.] 



Not present in the Pacific plankton, but found at six sur- 

 face stations in the tropical Atlantic. The structure of the 

 fifth legs in both sexes will serve to distinguish the species. 



Pontellopsis regalis (Dana) 

 (Figures 88, 92) 



[Pontella regalis Dana, Proc. Amer. Acad. Arts and Sci., \ol. 



2, p. 31, 1849.] 

 \Potitellina regalis Dana, U. S. Exploring Exped., 183S-1842 



(Wilkes), vol. 14, pt. 2, Crustacea, p. 1154, 1853; pi. 81, fig. 



!(?, b, 1855.] 



Found at two stations in the tropical Atlantic south of the 

 Sargasso Sea and at four in the eastern tropical Pacific. All 

 the specimens were taken at the surface. This is the largest 

 species of the genus and may be recognized by the structure 

 of the fifth legs. 



Pontellopsis villosa Brady 

 (Figure 91) 



[Pontellopsis villosa Brady, Voyage of H.M.S. Challenger, 

 Zool., vol. 8, pt. 23, Copepoda, p. 86, pi. 34, figs. 10-13; p'-, 

 35, figs. 14-20, 1883.] j 



A few specimens, including both sexes, were taken in the 

 surface tow at station 144, in the Pacific north of the Ha- 

 waiian Islands, and this was the only record for the cruise. 

 This was Brady's (1883, p. 86) original species which he 

 made the type of a new genus, Pontellopsis. His specimens 

 were obtained by the Challenger expedition in almost exactly 

 the same locality as the Carnegie specimens, but fifty years 

 before. 



C;enus PSEUDOCALANUS Boeck, 1872 



Pseudocalanus gracilis G. O. Sars 



[Pseudocalaniis gracilis Ci. O. Sars, Cru.'.t;icea of Norway, vol. 

 4, p. 154, suppl. pi. I, 1903.] 



Two females were found in the surface tow at station 46 

 in the eastern Pacific, and this was the only record for the 

 cruise. The number of specimens is far too small to warranfi 

 any general conclusions. With (1915, p. 57) considers thiJ 

 species a synonym of P. m:ntiti(s. % 



\ 



