FISHERY BULLETIN: VOL. 76, NO. 3 



Photosensitive Vesicles 



The vesicles have been described in detail by 

 Young (1972a). One set is present. They are lo- 

 cated in the dorsal wall of the mantle cavity at the 

 base of the funnel. Each organ consists of a small 

 cluster of spherical vesicles. 



Order Sepioidea 



Heteroteuthis hauaiiensis (Berry 1909) 



Vertical Distribution (Figure 47) 



The distribution of this species has been discuss- 



ed by R. E. Young ( 1977). During the day, speci- 

 mens ssl7 mm ML were taken between 250 and 

 350 m; larger specimens were taken between 375 

 and 650 m. At night, most specimens <17 mm ML 

 came from depths between 150 and 200 m; larger 

 specimens were taken between depths of 110 and 

 550 m. Males and females mature at about 15-16 

 mm ML. 



Photosensitive Vesicles (Figure 48) 



Two sets of organs are present (R. E. Young 

 1977). The more dorsal set lies on the posterior 

 margin of the peduncle complex and consists of a 

 short and narrow string of tiny vesicles. An even 



200 



E 



=E 400 



a. 

 uj 



600 

 SOOh 



10 12 U 16 18 



MANTLE LENGTH, mm 



20 



22 



Figure 47.— Vertical distribution of 

 Heteroteuthis hawaiiensis. From R. E. 

 Young (1977). Symbols as in Figure 1. 



24 



26 



Figure 48. — Photosensitive vesicles oi^ Heteroteuthis 

 hawaiiensis. In this figure the outline of portions of 

 the head and mantle are superimposed to give a clear 

 perspective of the peculiar arrangement of vesicles in 

 this species. EYE— eye; FUN.— funnel; MAN.— 

 mantle. Otherwise abbreviations as in Figure 2. 



MAN 



608 



