COPEPODS FROM EQUATORIAL WATERS OF PACIFIC OCEAN 



189 



described two new species and presented de- 

 scriptions of five hitherto unknown males. 

 Calocalaniis gracilis Tanaka, 1956, is not in- 

 cluded in her revision. 



Calocalanus plumulostis (Claus, 1863) 



(Plate 6, figs. 11-13) 



Pacific records: Scott, 1909; Farran, 1929; 1936; 

 Dakin and Colefax, 1940; Mori, 1942; Wilson, 1942; 



Anraku, 1953; Tanaka, 1953; Tanaka, 1956b; Hein- 

 rich, 1957b; 1958b; Yamazi, 1958a. 



Vessel : 



Satsuma 



Station Occurrence 



__ 32 2 females, 0.87 mm. 



Remarks: According to Bernard's revision 

 (see Remarks under preceding species), this 

 species belongs to a new genus, Leptocalanus. 

 The descriptions presented by Tanaka (1956b) 

 and Bernard (1958) of the male are quite dif- 

 ferent and the two are not unispecific. 



Family PSEUDOCALANIDAE 



Clausocalanus arcuicornis (Dana, 1849) 



(Plate 7, figs. 1-6) 



Pacific records: Vervoort, 1946; 1957. Also, Yamada, 

 1933; Johnson, 1942; Mori, 1942; Brodsky, 1950; Nakai, 



1952; Anraku, 1954b; Tsuruta and Chiba, 1954b; 

 Brodsky, 1955; Chiba, Tsuruta, and Maeda, 1955; Mo- 

 toda and Anraku, 1955; Nagaya et al., 1955; Rose, 

 1955; Chiba, 1956; Tanaka, 1956b; Heinrich, 1957b; 

 Honjo et al., 1957; Heinrich, 1958a; Yamazi, 1958a; 

 Brodsky, 1959; Lindberg, 1959; Ponomareva, 1959. 



Vessel : 



Hugh M. Smith 

 Do 



Do 



Do 



Do 



Do 



Do 



Do 



Stranger 



Orsom 10 



Horizon 32 



Station Occurrence (measurement in mm.; number of specimens in paren.) 



f. minor, f. major, 



female female male 



, 94 1.26-1.29(2) 



132 1.07-1.24(17) 



. 144 present 1.34-1.46(8) present. 



. 153 1.15-1.25(4) 1.37(1) 



. 178 1.08-1.28(21) 1.33(1) 



30 1.43-1.56(14) 1.21-1.26(2) 



. 31 1.19-1.31(4) 1.42-1.53(5) 



. 63 1.33(1) 1.51(1) 



. 34 1.16-1.28(10) 



1.16-1.24(13) 1.53(1) 



1.14-1.24(6) 1.30-1.46(2) 



Satsuma 



32 1.08-1.12(3) 



Remarks: I have tentatively equated the 

 females of this species to two forms which 

 were described by Sewell, 1929. The two forms 

 are distinguished by size and the total and 

 relative lengths of the segments of the fifth 

 feet. Forma major is large (1.30-1.60 mm.), 

 and the fifth pair of feet is small (fig. 2). The 

 distal segment is about twice as long as the 

 proximal one (fig. 3). Forma minor is dis- 

 tinguished by its small size and its longer fifth 

 feet (fig. 5) . The distal and proximal segments 

 are about equal in length. 



Tanaka (1956b) has described two types of 

 males of this species which differ in size and 

 in the structure of the fifth feet. Although rare 

 in the present collections, males with fifth feet 



referable to Tanaka's large form were found 

 in the sample from the Hugh M. Smith, sta- 

 tion 30. 



Clausocalanus furcalus (Brady, 1883) 



(Plate 7, figs. 7-8) 



Pacific records: Vervoort, 1946. Also, Mori, 1937; 

 1942; Wilson, 1942; Brodsky, 1950; Wilson, 1950; 

 Nakai, 1952; Anraku, 1953; Tanaka, 1953; Yamazi, 

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

 Alotoda and Anraku, 1955; Nagaya et al., 1955; Rose, 

 1955; Chiba, 1956; Tanaka, 1956b; Honjo et al., 1957; 

 Heinrich, 1958a. 



