254 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 117 



urosome segment 2 often asymmetrical. Female Al 17-segmented; 

 male right Al with 4 segments distal to geniculation. Ri of P1-P4 

 2-segmented. Female P5 uniramous, 3-4-segmented. Male P5 

 4-segmented, the 2 distal segments forming a chela. 



Calanopia americana Dahl 



Figures 5f-j 



Calanopia americana Dahl, 1894, p. 12, pi. 1, figs. 23-26.— A. Scott, 1909, p. 181, 

 pi. 48, figs. 11-15.— Esterly, 1911, pp. 222-223, pi. 2, figs. 12, 15; pi. 3, figs. 

 27, 32; pi. 4, fig. 39.— T. Scott, 1912, p. 537, pi. 13, figs. 1-6.— Farran, 1929, 

 p. 274.— Jesperson, 1940, p. 67.— Wilson, 1942, p. 172, fig. 2.— Davis, 1950, 

 pi. 91 (table).— King, 1950, p. 129 (table).— Car valho, 1952, p. 149, pi. 1, 

 figs. 37-39.— Wickstead, 1956, pp. 15-16.— Bowman, 1957, passim, fig. 3h.— 

 Woodmansee, 1958, p. 256.— Grice, 1960, p. 220.— Breuer, 1962, p. 167.— 

 Fish, 1962, pp. 17-18.— Bjornberg, 1963, pp. 58-59, fig. 30.— Reeve, 1964, 

 passim. 



Female. — Length 1.4-1.6 mm. Prosome : urosome = 2.8. Pointed 

 corners of PedSeg 5 relatively short. Genital segment shghtly 

 longer than posterior m:*osome segment. Distal segment of P5 ending 

 in 3 spines; middle spine much longer than others. 



Male.— Length 1.4 mm. Urosome segment 2 without processes. 

 Right Al, segment proximal to geniculation with strong process at 

 proximal end of anterior margin perpendicular to segment. P5 as in 

 figure 5j. 



Distribution. — Warmer parts of the western Atlantic. The most 

 northern record is Jesperson's rather surprising one south of Iceland 

 (62°40' N., 19°05' W.) . As Jesperson suggested, the 3 specimens were 

 very probably carried there by the Gulf Stream. South of Cape 

 Hatteras C. americana is found regularly along the coast and offshore 

 (unpublished observations). It occurs in the Gulf of Mexico, the 

 Caribbean, and south to the southern coast of Brazil (Bjornberg, 1963). 

 Smithsonian-Bredin Expeditions have collected it at English Harbor, 

 Antigua; Marigot Bay, Saint Lucia; and off Crown Point, Tobago. 

 A net tow made in Lameshm- Bay, Saint John, Virgin Islands, by 

 Dr. John Randall at our request obtained numerous specimens of C. 

 americana. 



In the Puerto Rico collections, C. americana was obtained only from 

 net tows made at night in Bahia Fosforescente. The collections from 

 Tobago, Saint Lucia, Antigua, and Saint John were also made at night. 

 Clarke (1934), working in Bermuda, found that during the day C. 

 americana lives very close to the bottom and probably buries itself in 

 the mud. At night it moves up close to the sm-face. The robust outer 

 spines on Re of P1-P4 may assist Calanopia in clinging to the bottom 

 during the day. 



