44 THE PHOSPHORESCENT ORGANS 



able to obtain sections clearly showing the cellular struct- 

 ure of what I have called the lens. But from the fact 

 that my studies have resulted in ascertaining that the or- 

 gans are probably phosphorescent in their nature, but dif- 

 fering in many respects from any previously described, 

 I have thought it best to publish them, without waiting 

 for ocular proof of their phosphorescence, or for better 

 specimens. 



In Porichthys the organs are arranged in regular lines 

 which follow to a large extent the distribution of the " lat- 

 eral line organs," and for purposes of description I have 

 given the various rows names by which they will be re- 

 ferred to in the following account. 



The two anal(a) rows run one along either side of the 

 anal fin, from just behind the vent to the base of the cau- 

 dal fin. Each row is composed of a double series of 

 organs, these being in pairs, but the outer ones are near- 

 ly twice the size of the inner. 



The pleural (pi) row starts beneath the pectoral fin, 

 runs upward and backward in an arcuate line, and then 

 runs horizontally along the side of the body to a point 

 about opposite the twentieth ray of the anal fin. The or- 

 gans in this row are single. 



The lateral row (I) follows the normal lateral line from 

 a point just behind the level of the base of the pectoral to 

 the caudal. It consists of a triple series of organs, the 

 middle of which are the ordinary mucous pores of the lat- 

 eral line, the lower and upper, however, being phosphores- 

 cent organs. The lower series of organs are larger than 

 the upper, which are like those in the row described below 

 as occipital. 



The dorsal row(eZ) follows the base of the dorsal fin, and 

 though it is but a single series, it consists of alternating 

 phosphorescent organs and mucous pores. 



