176 CHARLES DARWIN 



of rest, I suppose this beautiful and most anomalous struc- 

 ture is adapted to take hold of floating marine animals. 



In deep water, far from the land, the number of living 

 creatures is extremely small: south of the latitude 35, I 

 never succeeded in catching anything besides some beroe, 

 and a few species of minute entomostracous crustacea. 

 In shoaler water, at the distance of a few miles from the 

 coast, very many kinds of crustacea and some other animals 

 are numerous, but only during the night. Between latitudes 

 56 and 57 south of Cape Horn, the net was put astern 

 several times ; it never, however, brought up anything besides 

 a few of two extremely minute species of Entomostraca. 

 Yet whales and seals, petrels and albatross, are exceedingly 

 abundant throughout this part of the ocean. It has always 

 been a mystery to me on what the albatross, which lives far 

 from the shore, can subsist ; I presume that, like the condor, 

 it is able to fast long ; and that one good feast on the carcass 

 of a putrid whale lasts for a long time. The central and 

 intertropical parts of the Atlantic swarm with Pteropoda, 

 Crustacea, and Radiata, and with their devourers the flying- 

 fish, and again with their devourers the bonitos and albi- 

 cores; I presume that the numerous lower pelagic animals 

 feed on the Infusoria, which are now known, from the 

 researches of Ehrenberg, to abound in the open ocean: but 

 on what, in the clear blue water, do these Infusoria subsist? 



While sailing a little south of the Plata on one very dark 

 night, the sea presented a wonderful and most beautiful 

 spectacle. There was a fresh breeze, and every part of the 

 surface, which during the day is seen as foam, now glowed 

 with a pale light. The vessel drove before her bows two 

 billows of liquid phosphorus, and in her wake she was fol- 

 lowed by a milky train. As far as the eye reached, the crest 

 of every wave was bright, and the sky above the horizon, 

 from the reflected glare of these livid flames, was not so 

 utterly obscure as over the vault of the heavens. 



As we proceed further southward the sea is seldom phos- 

 phorescent; and off Cape Horn I do not recollect more than 

 once having seen it so, and then it was far from being bril- 

 liant. This circumstance probably has a close connection 

 with the scarcity of organic beings in that part of the ocean. 



