BIOLOGY. 293 



DEEP-SEA DREDGINGS. 



At the last meetino^ of the British Association, a letter was read 

 from Prof. Wyville Thomson on recent dredging in 2,435 fathoms. 



The remarkable extension of knowledge in this direction had 

 removed the idea which, started by the late Prof. Forbes, had 

 prevailed till very recently, that marine life did not exist at depths 

 beyond 300 fathoms. That was a most remarkable illustration of 

 the necessity for caution in coming to conclusions. If Prof. Forbes 

 could fall into such an error, how careful needed every one to be in 

 comins: to conclusions ! Some interestino^ results had been ob- 

 tained by Prof. Percival Wright off the coast of Spain ; and H. M. S. 

 *' Lightning" had been sent out to dredge in the sea between the 

 Hebrides and the Faroe Islands ; and one result was, to find that 

 there were two distinct sets of temperature and two sets of fauna 

 within 50 miles ; that difference of temperature was probably 

 caused by the return of the waters of the Gulf Stream, after being 

 cooled at the Pole. The investii^ations of the *' Lisfhtninjj" had 

 only been carried to the depth of 650 fathoms, and found no life 

 at that depth. Prof. Thomson had, however, dredged in the Bay 

 of Biscay to the depth of 2,800 fiithoms; and the letter gave an 

 interesting account of the casting of the dredge at such depth. 

 Above one and one-half cwt. of ooze was the general result of a cast 

 of the dredge, and the thermometric instruments employed showed 

 the temperature to be about 36.4; and life was distributed over 

 the whole area which had been examined before the specimens 

 were of a dwarfed character, owing, probfibly, to the low tem- 

 perature. In the course of the discussion wliich ensued, Prof. 

 Huxley said he hoped it would not be at once assumed that natu- 

 ralists had assumed Prof. Forbes' inference as to the depth at 

 which life might be expected to exist. No revolution had taken 

 place in science on account of the recent dredgings. Men of 

 science — and even Prof. Forbes himself — were too well aware 

 of the unsatisfactory nature of the merely negative evidence, of 

 which they were always distrustful. 



He had recently had the opportunity of examining a quantity 

 of soundings sent him by the Admiralty, which had been dredged 

 in all parts of the world ; and it appeared from these that there 

 was a gigantic band of life encircling the globe at the bottom of 

 the sea. It was, too, extremely interesting to reflect that the sea 

 bottom in which these creatures were found was of the same geo- 

 logical formation as that which was millions of years old ; and the 

 forms of life found there also resembled those found in the geo- 

 logical formations, called the cretacean period. 



THE AMCEBA. 



The following extracts on this singular creature are from the 

 ♦* London Quarterly Review " : — 



"Perhaps the clearest instance of the uselessness of attempting 

 25* 



