FISHES OF THE PHILIPPINE ISLANDS AND ADJACENT SEAS 271 



well behind ventral, not reaching caudal ; caudal oi/^ in rest of body, 

 with slight notch in upper lobe behind, subcauclal forming distinct 

 lobe; pectoral short, partly truncate, angles rounded; ventral larger 

 than dorsals. 



Color dull vinaceous brown above, paler below. Dark color of 

 back extends as band completely encircling gill openings and same 

 region of pharynx. Fins colored dark like back, excejDt pectoral 

 which pale greenish on under surfaces and hind portions above, also 

 borders of most of other fins. Iris dusky, large pupil green. 



Mauritius, Australia, Lord Howe Island, Hawaii. Also in the 

 tropical Atlantic. 



"Wlien the larger specimen, taken at night, was removed into a 

 dark apartment, it afforded a very extraordinary spectacle. The en- 

 tire inferior surface of the body and head emitted a vivid and green- 

 ish phosphorescent gleam, imparting to the creature, by its own light, 

 a truly ghastly and terrific appearance. The luminous effect was 

 ■constant, and not perceptibly increased by agitation or friction. I 

 thought, at one time, that it shone brighter when the fish struggled, 

 but I was not satisfied that such was the fact. AVhen the shark 

 expired (which was not until it had been out of the water more than 

 three hours) the luminous appearance faded entirely from the ab- 

 domen, and more gradually from other parts; lingering the longest 

 around the jaws and on the fins. 



"The only part of the under surface of the animal which was free 

 from luminosity was the black collar around the throat; and while 

 the inferior surface of the pectoral, anal, and caudal fins shone with 

 splendour, their upper surface (including the upper lobe of the tail 

 fin) was in darkness, as also were the dorsal fins, back and summit 

 of the head. 



"I am inclined to believe that the luminous power of this shark 

 resides in a peculiar secretion from the skin. It was my first im- 

 pression, that the fish had accidentally contracted some phosphores- 

 cent matter from the sea, or from the net in which it was captured ; 

 but the most rigid investigation did not confirm this suspicion ; while 

 the uniformity with which the luminous gleam occupied certain por- 

 tions of the body and fins, its permanence during life, and decline 

 and cessation upon the approach and occurence of death, did not 

 leave a doubt in my mind that it was a vital principle, essential to 

 the economy of the animal." (Bennett.) 



Since the above was written it has been found that the luminous 

 condition continued some hours after death. 



1 example. A.N.S.P. Honolulu, Hawaiian Islands. Bishop Museum. Length, 

 317 mm. 



