XX 



Obituary Notice of Fellow deceased. 



1400 fathoms and the latter 2900 fathoms, a similar depth having produced 

 fishes in the " Challenger." No part of this fine treatise is more interesting 

 than that in which the characteristics of the deep-sea fishes are portrayed 

 by the author., such as the size of the eyes, the black colour of the pharynx 

 and of the surface of the ccelom, the fibrous, fissured, and cavernous structure 

 of the feebly developed bones, the thin lateral muscles, and the loose 

 connection of the vertebrae. As a consequence, when they are drawn to the 

 surface these specimens require the most careful manipulation to prevent 

 their breaking into fragments. Yet under the normal conditions of their 

 abyssal home, that is under the enormous pressure of the surrounding 

 element, the fibro-osseous tissues and the thin muscles suffice for rapid and 

 powerful movements. When drawn up the expansion of the gases in the 

 air-bladder causes the gullet and stomach to be thrust out of the mouth and 

 the eyes from their sockets. These deep-sea fishes possess a largely developed 

 muciferous system on head and body, and in addition a series of phosphor- 

 escent organs. Dr. Giinther gives a lucid and comprehensive description of 

 the modifications of these organs as to distribution, appearance and structure, 

 grouping his remarks under nine heads. He considered that these fishes 

 contribute to a considerable extent to the luminosity of the abyssal depths, 

 and that such light enables the possessor to see ; and in those in which the 

 organs are highly developed and specialised, the light is under the will of 

 the fish, which thus can use its " searchlight " for the purpose of discovering 

 prey or for other purposes. Further, the occurrence of such organs in the 

 cavities of the gills or within the mouth does not invalidate such a view, as 

 the membranes and bones are semitransparent. On the other hand, he 

 pointed out that the luminous organs which are placed on barbels, filamentous 

 fin-rays, or tentacles serve as lures, and that even those on the caudal 

 peduncles of Scopelids, Sternoptychids, and others probably have the same 

 function. 



Another notable observation of Dr. Giinther's was the reduction of the gill 

 laminae in these fishes : the horny rods which support the plaits of the mucous 

 membrane being deficient in firmness, the laminae are reduced in number and 

 the respiratory surface diminished. He was inclined to associate this with 

 their sojourn in the low temperature of the abyssal depths and its effect on 

 circulation and respiration. He also points out that the spawn of some of 

 them (e.g. Polyprion cemium) develops at the surface, whilst the young fishes, 

 after a short pelagic existence, descend to the bottom as in the flat fishes. 

 He considers, however, that in others the spawn will be deposited on the 

 bottom and hatched there, thus affording an extreme contrast to the former, 

 which were developed under the accelerating influences of light, warmth, and 

 a constant supply of oxygen. The oviposition and hatching of the eggs of 

 fishes, indeed, are marvellous in their infinite variation. 



Equally interesting are his remarks on the vertical and horizontal distri- 

 bution of these deep-sea fishes, the families, for instance, which descend to 

 the greatest depth, viz. 2900 fathoms, are Berycidae, Pediculati, Ophidiid;e, 



