CHAETOGNATHA COLLECTED BY STEAMER ALBATROSS. 



257 



less than number of teeth. Wing of ridge covers all except the 

 first and occasionally the second tooth. Notch extends to the 

 fourth or fifth tooth. External process short and blunt, not, as 

 described by Fowler (1906, p. 6), "terminating externally in a well- 

 marked, rather sharp process." Its length is about two-sevenths 

 that of entire ridge. 



Anterior teeth 8 to 10 and posterior teeth (pi. 37, fig. 20) 20 to 28 

 in number in individuals 10 to 15 mm. long. Anterior teeth are 

 closely set and diverging distally, while the posterior teeth are more 

 closely set and only slightly divergent distally. 



Seizing jaws (pi. 37, fig. 24) 5 to 7 in number. Points with curved 

 tip, oval bases, and embedded about 25 per cent of then- heights 

 into shaft. Base of point and top of shaft parallel. Pulp-canal 

 central, extending into point about 75 per cent of its height and 

 converging markedly toward edge of point. Pulp evenly distributed 

 throughout canal. 



TABLE 11. Measurements of Sagitta bedoti. 1 



i S 



I 



29 

 25 



25 



25. r. 



25 

 20 



25. 



eg 



24.7 4.0 



24 4.5 



27 3 



23.5 4 

 26 



14.4 

 16 

 14.5 

 , 15 

 14 

 16 

 15.5 

 16.5 

 16.5 

 15.5 



9-10 

 9-9 

 9-10 

 S-9 



24-22 

 24-23 

 27-28 

 22-21J 

 24-25! 

 25-24 

 22-21 

 24-25 

 23-22i 



20-21; 



1 All measurements made in per cent of total length of animal. 



2 Ter cent of posterior fin in front of tail-septum. 



Distribution. S. ~bedoti was collected from only four stations, 352 

 specimens having been obtained. As shown by the following table 

 all specimens were taken from the upper epiplankton. This indica- 

 tion that the species typically occurs near the surface is supported 

 by other expeditions and collections. It has been taken near the 

 surface in the region of Port Natal by the Gauss expedition; in the 

 Maldive and Laccadive Archipelagoes by Doncaster (1902) under the 

 name S. polyodon; in the Malay Archipelago by Beraneck (1895) ; 

 in the Siboga region by Fowler (1906) ; in Misaki Harbor, Japan, by 

 Aida (1897) under the name S. lipunctata; and in Sharks Bay, 

 Australia, by Ritter-Zahony (1910). Altogether, the evidence war- 

 rants concluding that S. 'bedoti is characteristic of the upper epi- 

 plankton of the tropical Indo-Pacific region. 



