February 29, 19 12] 



NATURE 



597 



A SELF-CLOSING PLANKTON NET FOR 

 HORIZONTAL TOWING. 



A SELF-CLOSING plankton net has long been needed 

 "^ for horizontal towing. It is especially necessary for 

 the investigation of the vertical distribution of pelagic 

 organisms. Numerous attempts have therefore been made, 

 from the time of Pavesi (1883) onward, to devise a satis- 

 factory instrument for this purpose. The latest, and 

 apparently the most satisfactory one of its kind, has been 

 designed by Prof. Kofoid after suggestions from Dr. G. H. 

 Fowler, of the Research expedition. 



The net is a ring net with circular opening, which can 

 be both opened and closed under water by messengers. 

 The bag of the net is, as usual, of silk bolting cloth, a 

 simple cone held horizontally by a support. The frame is 

 a heavy casting of phosphor bronze, with enlargements at 

 the horizontal axis for the reception of the hubs of the 

 jaws of the net. The upper end of the frame is expanded 

 to form a head-piece enclosing and protecting the tripping 



A Self-closing Plankton net. 



mechanism for the net jaws, and the lower edge bears a 

 slot for attaching the heavy weights. 



The net is balanced in a vertical position by the very 

 heavy lower flatiron-shaped weight. 



'i'he mouth of the net is formed not by one continuous 

 ring, but by two hinged jaws, which can both be brought 

 up and held together by the tripping apparatus. In the 

 figure both jaws are in this position, and the net mouth 

 is closed, the net being ready for descending. The two 

 semicircular jaws can rest in three positions : they may 

 be both folded against each other and held upwards as in 

 the figure, or one may be allowed to fall forwards and 

 downwards until both jaws complete a circle and the net 

 mouth is open. In the third position both jaws lie against 

 each other, but hang downwards. 



There are two " trips," one of which is operated by the 

 first messenger, the other by the second. 



The net is lowered vertically, the ship being at rest, to 

 the desired depth, and the first messenger sent down the 

 cable. This releases the lower jaw, which falls forwards 

 and downwards until the net mouth is open. 



After towing is completed and the cable is perpendicular, 

 the second messenger is sent down, and the upper jaw is 

 released. It falls to the lower position, is held firmly 

 against the lower jaw, and thus the net is closed. 



NO. 2209, VOL. 88] 



The advantages which this net possesses over other 

 models are stated by Kofoid to be : — 



(i) A method of opening and closing at any level in the 

 sea under complete control of the operator. 



(2) Perfect and continuous closure of the net during 

 descent and ascent. 



(3) Possibility of horizontal towing. 



(4) An opening free from interfering structures which 

 tend to ward off more active pelagic animals. 



W. J. D. 



TBE ANTHROPOLOGICAL SURVEY OF 

 CANADA. 



^PHE Dominion of Canada is the first of our colonies to 

 have an official department for the sole purpose of 

 anthropological investigation, and it is to be hoped that 

 this good example will be followed speedily elsewhere. 

 The history of this new departure is briefly as follows. 



When the British Association met at 

 Montreal in 1884, a committee, con- 

 sisting of Dr. E. B. Tylor, Dr. G. M. 

 Dawson, General Sir J. H. Lefroy, Dr. 

 Daniel Wilson, Mr. Horatio Hale, and 

 others (the personnel of which was sub- 

 sequently modified), was appointed for 

 the purpose of investigating and pub- 

 lishing reports on the physical 

 characters, language, industrial and 

 social condition of the north-western 

 tribes of the Dominion of Canada. The 

 twelfth and final report of the com- 

 mittee was presented at the Bristol 

 meeting in 1898, which, in addition to 

 original articles, contained a summary 

 of the work of the committee in British 

 Columbia by Dr. F. Boas, and an index 

 to reports iv.-xii. In view of the meet- 

 ing of the association in Toronto in 

 1897, a new committee, consisting of 

 several Canadian and British members, 

 was appointed at the Liverpool meeting 

 in 1896 " to organise an ethnological 

 survey of Canada," of which Dr. 

 George M. Dawson was chairman and 

 secretary. Prof. D. P. Penhallow was 

 elected chairman in 1899. The com- 

 mittee suffered a great loss by the 

 death of Dr. Dawson in 1901 ; he was 

 succeeded by Mr. C. Hill-Tout. Prof. 

 J. L. Myres, in his presidential address 

 to Section H at Winnipeg, gave a 

 short history of the work of the two 

 committees, and stated that " the pre- 

 mature death of George Dawson in 1901 

 broke the mainspring of the machine ; 

 the field-workers fell out of touch with one another and with 

 the subject ; the instruments were scattered, and in 1904 the 

 Ethnographic Survey Committee was not recommended for 

 renewal.*" Thanks mainly to the energy of Prof. J. L. 

 Myres and Mr. E. S. Hartland, a third committee was 

 appointed at Winnipeg, 1909, with the Rev. Dr. G. Bryce 

 as chairman and Mr. Hartland as secretary. The Ethno- 

 graphic Survey Committee reported at the Sheffield meet- 

 ing in 1910 (Report, p. 265) that its work had been 

 crowned with success. The recommendations of this com- 

 mittee at the Winnipeg meeting to the Dominion Govern- 

 ment were supported by delegations of the Canadian 

 section of the Archaeological Institute of .America and the 

 Royal Society of Canada, and on September i, 1910, a 

 division of anthropology under the Geological Survey of 

 Canada was established, of which Dr. E. Sapir was made 

 director. Dr. Sapir is a distinguished student trained by 

 Prof. F. Boas. Dr. Boas is himself intimately acquainted' 

 with Canadian ethnology, and in 188S, under the auspices 

 of the committee of the British .Association, began his field- 

 work among the north-vv^est tribes which has led to such 

 brilliant results. The inauguration of the new department 

 could not have been put in better hands, but the work 

 was clearly too vast for one man to cover it. On January 

 I, 191 1, Mr. C. M. Barbeau, a very promising Canadian 



