70 



BULLETIN 11, UNITED STATES NATIONAL MUSEUM. 



Genus JACULELLA H. B. Brady, 1879. 



Jaculella H. B. Brady (type, /. acuta H. B. Brady), Quart. Journ. Micr. Sci., 

 vol. 19, 1879, p. 35. — Butschli, in Bronns Klassen und Ordnungen des 

 Thierreichs, vol. 1, 1880, p. 193.— H. B. Brady, Rep. Voy. Challenger, 

 Zoology, vol. 9, 1884, p. 255.— Rhumbler, Arch. Protistk., vol. 3, 1903, p. 

 273. 



Description. — Test free, elongate, conical, widest at the apertural 

 end, opposite end closed; wall thick, composed of sand grains roughly 

 cemented on the exterior. 



In Jaculella the distinction between proloeulum and tubular cham- 

 ber is not as marked as in some of the other genera, but in J. obtusa 

 the relation is often made out more definitely. There are but two 



described species, both of which are re- 

 corded from the North Pacific, though 

 but rarely. 



JACULELLA ACUTA H. B. Brady. 



Jaculella acuta II. B. Brady, Quart. Journ. 

 Micr. Sci., vol. 19, 1879, p. 35, pi. 3, figs. 

 12, 13.— Goes, Kongl. Svensk. Vet. Akad. 

 Handl., vol. 19, no. 4, 1882, p. 143, pi. 

 12, fig. 432.— II. B. Brady, Rep. Voy. 

 Challenger, Zoology, vol. 9, 1884, p. 255, 

 pi. 22, figs. 14-18.— Goes, Bull. Mus. 

 Comp. Zool., vol. 29, 1896, p. 23.— Flint, 

 Rep. U. S. Nat. Mus., 1897 (1899), p. 269, 

 pi. 9, fig. 4. — Rhumbler, Arch. Protistk., 

 vol. 3, 1903, p. 273, fig. 122 (in text). 



Description. — Test elongate, straight, 

 tubular, proximal end closed and acutely 

 pointed, distal end broader, slightly con- 

 stricted to form the aperture which is 

 circular, wall thick, composed of coarse 

 sand grains, firmly cemented, exterior 

 rough, proximal end of the test often 

 reddish-brown, distal portion grayish. 



Length variable, up to 25 mm. or even 

 more. 



Distribution. — Brady records this spe- 

 91 cies at but one North Pacific Challenger 

 station, 244, in 2,900 fathoms, in mid- 

 x 12 Pacific. I have seen two specimens 

 from Albatross station H2684 in 1,122 

 fathoms and H2917 in 2,615 fathoms, one off the coast of Califor- 

 nia, the other near the Hawaiian Islands. 



The closed end of the specimens seems to be easily detached as 

 they are rarely found complete. 



3$ 



90 



Figs. 90-91.— Jaculella acuta, 

 (after Brady). 



