574 DE. G. H. FOWLER ON THE [June 21, 



future use (4+6) 10 Ibs. ; suggested above to be added at T'T', 

 10 Ibs., and to be hung on C, 10 Ibs. : total about 80 Ibs. 



At the conclusion of the four hauls, the net was sent down to 

 100 fathoms, and hauled up without the messengers having been 

 despatched ; it came up empty, although it had passed through 

 the stratum where life w T as probably most plentiful. I am unable 

 to see any source of error in the working of this apparatus, but 

 hope that it may be given a further trial before long *. Of course, 

 with an apparatus half a mile away from one in water, one cannot 

 see what is actually occurring ; one can only take precautions 

 against every possible source of error, and may judge of their 

 success to some extent by the character of the animals obtained. 



Conclusions of Prof. Agassiz : the Azoic Zone. 



In discussing the general results of the ' Albatross ' Expedition in 

 1891 2 , Prof. Agassi/, reviewed the apparatus used and conclusions 

 attained by earlier naturalists who had attempted a solution of the 

 question of a Mesoplankton. His own views are based on experi- 

 ments made during the cruises of the ' Blake' (1877-80) and the 

 * Albatross ' (1891). On the first of these vessels he used the gravi- 

 tating-trap 3 invented by Lieutenant-Commander (now Captain) 

 Sigsbee, which not only failed to catch living organisms between 100 

 and 150 fathoms, but apparently missed even the corpses of the dead 

 surface fauna ! The machine is only stated to have been tried on 

 two occasions, and only to a depth of 150 fathoms ; from this 

 Agassiz concluded 4 (p. 37) that " these experiments serve to 

 prove that the pelagic fauna does not extend to considerable 

 depths, and that there is at sea an immense intermediate belt in 

 which no living animals are found, nothing but the dead bodies 

 which are on their way to the bottom." On the ' Albatross ' a 

 new apparatus was tried, the invention of Captain Tanner, which 

 is fully described and figured by Prof. Agassiz. On the basis of 

 this he states 4 (p. 55) : " Our experience in the Grulf of Cali- 

 fornia with the Tanner self-closing net would seem to indicate 

 that in a comparatively closed sea, at a small distance from the 

 land, there may be a mixture of the surface species with the free- 

 swimming deep sea bottom species, a condition of things which 

 certainly does not exist at sea, in deep water, in an oceanic basin at 

 a great distance from shore, where the surface pelagic fauna only 



1 The cost of the apparatus should come to about 10, now that the patterns 

 for casting have been made. If any zoologist will give it a further trial, I shall 

 be glad to superintend its manufacture. 



Sirce the above was written, my net has been taken for a further trial by 

 the German Expedition which sailed on August 1st under Prof. Chun's 

 direction, and Prof. Max Weber has ordered a net for the Dutch East-Indian 

 Expedition. 



2 Bull. Mus. Comp. Zool. Harvard, xxiii. 1. 



3 Bull. Mus. Comp. Zool. Harvard, xiv. 36 (=' Three Cruises of the Blake,' 

 vol. i. p. 36, London, 1888, 8vo). 



4 Bull. Mus. Comp. Zool. Harvard, xxiii. 1, 



