4i8 



DEPTHS OF THE OCEAN 



Species found 

 on both sides 

 of the North 

 Atlantic. 



Abyssal forms 

 have a con- 

 siderable 

 vertical 

 distribution. 



"Challenger' 

 hauls in the 

 deep water 

 of the North 

 Atlantic. 



Bathypterois longipes, Macrti^nis simulus, and Macrtcnis brevibar- 

 bis, are now known from both sides of the Atlantic. The three 

 last-mentioned species were also caught near the Azores, and we 

 must therefore conclude that their habitat stretches right across 

 the Atlantic. Macrurus csqualis was previously known only 

 from the eastern side, Macrurus globiceps also from the Azores, 

 and during the cruise of the " Michael Sars " it was taken a 

 little north of the latter locality (Station 88). If the above 

 table is compared with the list of " Michael Sars" stations, it 

 will be noticed that these fishes from the abyssal region have 

 a considerable vertical distribution, occurring also on the 

 continental slopes. 



Sir John Murray has, in his excellent "Summary," given 

 lists recording all the different animals captured at each of the 

 " Challenger " stations, and in a final chapter he endeavours to 

 lay down some of the most important laws governing the distri- 

 bution of animals in the ocean. At twenty-five stations where 

 the depth exceeded 2500 fathoms the "Challenger" took with 

 dredge and trawl 600 individual animals of all kinds ; this gives 

 24 individuals per haul. Now, firstly, many of these were 

 pelagic (most of the crustaceans and some of the fishes), and 

 secondly, many of them were very small (hydroids, bryozoa). 

 As examples I give a list of the bottom-forms (protozoa 

 excluded) obtained at some of the "Challenger" stations 

 between the Canaries and the West Indies. 



Station 5. Depth, 2740 fathoms. Three living mussels {Leda, Limopsis, Area), 



and some dead shells. 

 „ 13. Depth, 1900 fathoms. Some bryozoa and brachiopods (10 Tere- 



bratiila). 

 „ 14. Depth, 1950 fathoms. Some bryozoa. 

 „ 16. Depth, 2435 fathoms. Sharks' teeth {Oxyrhina, Lamna\ valves of 



Scalpellum, 2 mussels {Area). 

 „ 20. Depth, 2975 fathoms. Dredge came up half full of clay, containing 



half a dozen tubes of serpulids, some of these with the worms 



living. 

 ,, 61. Depth, 2850 fathoms. Trawl captured some ophiuridte (6^////^^/)7^//rt'), 



2 holothurians, 7 Sealpellum. 

 „ 63. Depth, 2750 fathoms. Trawl captured some fragments of worms, 3 



Scalpelhim, i fish {Halosaiirus rostratus). 



This list is representative of most deep-sea hauls, and their 

 uniform poverty is only broken by rare exceptions, as in a note- 

 worthy haul taken by the " Challenger " in the Pacific, between 

 Japan and Hawaii, at Station 244, in 2900 fathoms, which 

 gave :— 



