150 THE AMERICAN MONTHLY [August, 



cent. ' On tempestuous nights the phosphorescence, intensified by the 

 motion of the vessel, adds singulai'ly to the wildness of the scene. Each 

 wave rises like a mass of molten iron and seems to threaten the vessel with 

 destruction ; it breaks, then passes oft' in her trail, and adds new beauty to 

 her brilliant wake.' Among these are many creatures unknown to the zool- 

 ogist of fresh-water or the northern shores, forms of curious shape or beau- 

 tiful color. Physalia and the ' Portuguese man-of-war' and Porpita floating 

 medusas, Ars^onauta^ Atlanta^ and Janthina mollusks which never seek 

 the shore, and see it only when borne there to their own destruction by the 

 o-ale ; the innumerable mici-oscopic forms of animal and plant life, among 

 them Globlgerina and the other protozoa, and all the host of minute creatures, 

 both larval and adult. We must mention, for their beauty, also, the irides- 

 cent ctenophores, perhaps the most beautiful of all marine surface forms, for 

 the wonderful play of colors along the rows of locomotive paddles. 



On the physiology of deep-sea life, the following tacts are established : — 

 Man inhabits the depths of the air while deep-sea animals inhabit the deep 

 sea, but the conditions are very unlike ; on land we have extreme variation 

 of temperature ( — 78° F. + 120° F.), while in the sea depths the temperature 

 is practically uniform, while on the other hand, pressure range is slight on 

 land and very variable at different levels in the water. Animals at the sea- 

 bottom are subject to enormous pressure ; at 1,000 fathoms it is estimated to 

 be one ton per square inch. But marine animals whose bodies are permeated 

 by fluids readily adapt themselves to these immense pressures. Fishes and 

 mollusks suffer most from sudden removal from them. The latter come up 

 in a dredge with swim-bladder protruding from the mouth, eyes forced out of 

 their sockets, and scales fallen off' the body. It is thought that light penetrates 

 only to a depth of 200 fiithoms, but faint rays of certain colors may reach 

 o-reater depths. Since many deep-sea animals are phosphorescent, some 

 have thought they were able to slightly illuminate the dark depths. It is 

 true that many of the deep-sea bottom animals, from great depth, have eyes 

 which are constructed like those of their allies on land or at the surface ; 

 usually, however, their eyes are larger, as if to collect more light. Some 

 deep-sea forms are blind ; so, also, are others dredged from a depth of less 

 than 200 fathoms. They are very likely creatures which live in the mud, 

 and do not wander about at large. These blind ones, many of them, give 

 evidence of a much more delicate tactile sense to compensate the visual de- 

 ficiency. While whites, reds, oranges, greens, and greys are found among 

 the colors of marine animals, blues are never met except in a few pelagic 

 forms ; this is the more odd because of the protection it might be from re- 

 semblance to the color of the sea. The distribution of marine plants plays 

 an important part in the food supply of shore animals ; carnivorous animals 

 living upon animal feeders. It is therefore curious to notice that vegetable 

 life is entirely wanting from the population of the deep sea, hence the source 

 of food of the deep-sea forms becomes an interesting problem. It is found 

 that the dead carcasses of even very light animals will sink to the bottom of 

 the sea still fresh enough to supply a large amount of food for bottom car- 

 nivoi-es, and the fiiuna of the surface thus becomes a medium for the transfer 

 of food manufactured by surface vegetation ; also to the foraminifera and 

 sponges of the bottom a sort of ' broth,' formed of partly decomposed mat- 

 ters from the surface and along the shores, is distributed by the ocean currents, 

 and this probably remains serviceable for a long time, putrefaction being 

 very slow. 



The entire second volume is taken up with the description of characteristic 

 animals of the deep sea and the wonderful illustrations of some of the crea- 

 tures described, many of which are remarkably unlike the surface and shore 



