470 WESLEY R. COE AND STANLEY C. BALL 
VASCULAR SYSTEM 
The blood vascular system has been so fully described by 
Cravens and Heath (’06) for N. pelagica and correctly, although 
in less detail, by Birger (’09) for N. minima, that it is unneces- 
sary for us to state further than that we have verified their 
descriptions. ‘Figure 1 shows the anterior anastomosis (cv) in 
front of the brain, the junction of lateral and median vessels just 
back of the brain, and the posterior anastomosis of median (mv) 
and lateral (lv) vessels above the posterior portion of the intestine 
in the caudal fin. 
Nephridia seem to be lacking in all bathypelagic species. 
NERVOUS SYSTEM 
The brain and lateral nerve cords are essentially as described 
for N. pelagica by Cravens and Heath (’06). Both dorsal and 
ventral commissures are well developed (fig. 14). Near their 
origin from the brain lobes the lateral nerves bend sharply out- 
ward toward the lateral margins of the body, whence they con- 
tinue backward in a ventrolateral position beneath the intestinal 
diverticula and directly lateral to the blood-vessels (figs. 1, 10) 
nearly to the extremity of the body. In sexually mature males 
the lateral nerves (fig. 6, In) are forced dorsally from their normal 
positions by the fully developed spermaries, resuming their ven- 
trolateral positions immediately posterior to the gonads. In 
the posterior half of the caudal fin they bend dorsally above the 
most posterior intestinal diverticula to unite in a well-developed 
commissure (figs. 1, 8, In) above the intestine immediately 
anterior to the rectum. 
The nerves leading to the tissues of the head, to the proboscis, 
to the lateral tentacles, and to the body musculature are large 
and are quite conspicuous in sections as they pass through the 
body parenchyma. 
The fibrous central core of the lateral nerves is divided dis- 
tinctly into a smaller dorsal and a larger ventral portion, well 
separated by ganglion cells (figs. 6). The dorsal core gradually 
becomes proportionately smaller than the ventral the farther 
