COPEPODS FROM EQUATORIAL WATERS OF PACIFIC OCEAN 



199 



streetsi by its low crest, the smoothly rounded 

 posterior thoracic margins and the presence of 

 but 1 external spine on the first exopodal seg- 

 ment of the first feet. Except for the posterior 

 thoracic margins, which have 1 small projec- 

 tion (figs. 7-9), my specimen agrees with 

 Sewell's ivdica. In details of the mouth parts, 

 two minor differences were noted. Sewell's 

 specimens have 6 setae on the outer lobe of the 

 second antenna, while the present specimen has 

 7 (fig. 10) ; the exopod of the mandible has 9 

 setae (Sewell probably referred to the distal 

 segment) ; the present specimen has 10, one of 

 which is extremely small (fig. 11). 



The projections on the posterior thoracic 

 margins may be a variable character as Ver- 

 voort (1957) has observed in several species of 

 a related genus, Undeuchaeta. It seems best 

 therefore to refer the present species to C. in- 

 dica. 



Undeuchaeta plumosa (Lubbock, 1856) 



(Plate 12, figs. 1-14) 



Pacific records: Vervoort, 1957. Also, Brodsky, 1950; 

 Heinrich, 1957b; Tanaka, 1957b. 



Vessel: Station Occurrence 



Hurjh M. Smith __ 63 1 male, 3.52 mm. 



Horizon 32 1 female, 3.47 mm. 



Satsiima 32 1 female, 3.41 mm. 



Remarks : The female is distinguished by the 

 presence of a spine on the right side of the 

 genital segment (figs. 1, 2) near the dorsal 

 surface, and the male by the structure of the 

 fifth feet (figs. 12-14). 



Undeuchaeta intermedia A. Scott, 1909 



(PLATK 12, FIGS. 15-18) 



Pacific records: Vervoort, 1957. Also, Johnson, 

 1942; Brodsky, 1950 (as U. bispinosa) 



Vessel: Station Occurrence 



Hugh M. Smith __ 63 4 females, 3.99-4.28 



mm. 

 Horizon 32 3 females, 3.99-4.08 



mm. 



Remarks: The large ventral spine-like pro- 

 trusion of the genital segment in the female 

 (figs. 17, 18) distinguishes this species from 

 the preceding one. 



Family EUCHAETIDAE 



Euchaeta marina (Prestandrea, 1833) 



(Plate 13, fig. 1) 



Pacific records: Scott, 1909; Marukawa, 1921; Ya- 

 mada, 1933b; Mori, 1937; Dakin and Colefax, 1940; 

 Mori, 1942; Wilson, 1942; Brodsky, 1950; Motoda, 

 lizuka, and Anraku, 1950; Wilson, 1950; Anraku, 1952; 

 Honjo, 1952; Nakai, 1952; Anraku, 1953; Chiba, 1953b; 

 Tanaka, 1953; Anraku, 1954b; Tsuruta and Chiba, 

 1954b; Chiba, Tsuruta, and Maeda, 1955; Motoda and 

 Anraku, 1955; Nagaya et al., 1955; Rose, 1955; Chiba, 

 1956; Heinrich, 1957b; Honjo et al., 1957; Gilmartin, 

 1958; Heinrich, 1958a; Tanaka, 1958; Yamazi, 1958a; 

 Lindberg, 1959. 



Vessel : Station Occurrence 



Hugh M. Smith __ 132 1 male, 3.12 mm. 



Do 144 1 female, 3.61 mm. 



Do 153 2 females, 3.32, 3.42 



mm. 



Do 178 1 female, 3.06 mm. 



Do 30 3 females, 2.96-3.06 



mm. ;1 male, 2.99 

 mm. 



Do 31 present. 



Vessel: Station Occurrence 



Do 63 4 females, 3.40-3.60 



mm.; 1 male, 3.37 



mm. 

 Stranger 34 4 females, 3.13-3.26 



mm.; 5 males, 



3.06-3.23 mm. 

 Orsom 10 3 females, 3.13-3.23 



mm. 

 Horizon 32 2 females, 3.13, 3.23 



mm. 



Remarks: This is probably the most wide- 

 spread species in the genus. It occurred in ten 

 of the present samples and in two {Smith 153 

 and 30), it comprised a fairly significant per- 

 centage of the total number of copepods. 



Euchaeta wolfendeni A. Scott, 1909 



(Plate 13, figs. 2-9) 



Pacific records: Farran, 1936; Mori, 1937; Wilson, 

 1950; Honjo, 1952; Tanaka, 1953; Tsuruta and Chiba, 

 1954b; Chiba, Tsuruta, and Ma^da, 1955; Nagaya et 



