262 THE ZOOLOGIST. 



grounds. Moreover, he demonstrates that Dr. Petersen, an able 

 Danish fisheries' investigator, made an error in asserting that 

 the Plaice-fishery of the Cattegat, which was begun in 1876, had 

 reached its maximum, and was in 1894 declining. Dr. Petersen, 

 however, believes — it may be with reason — that overfishing may 

 occur when the numbers of fishes are stationary, or even in- 

 creasing, a condition which perhaps, in the face of facts, might 

 not be inappropriate for the scientific men in our country who 

 uphold the impoverishment of the sea. Dr. Kyle, then, found 

 in 1904 — ten years after Dr. Petersen's report — that not only 

 was the Danish Plaice-fishery as productive, but even more so, a 

 larger number of boats being employed ; and, as if to show the 

 resources of nature, a new Plaice-fishery by the Swedes along the 

 northern border of the same area had sprung up (since Dr. Peter- 

 sen's report), and was flourishing. In this interesting contribu- 

 tion by Dr. Kyle many facts of importance are brought out. 

 Thus, for instance, the quantities of Cod taken by Norway alone 

 are three times those of all the other countries round the North 

 Sea combined. He points out, moreover, the well-known fact 

 that trawls only fish on the bottom, and thus are unable to give 

 a complete account of the distribution of fishes, even on open 

 grounds. The conclusions of Dr. Kyle are substantiated by an 

 account, by A. C. Johansen, of the biology of the Plaice for 

 Denmark, for he shows that as soon as the Plaice-seine was 

 adopted by the fishermen (1872-80) the fishery grew apace. 

 Thus the total yield of the Danish Plaice-fishery was : — 



1887 1,048,000 kroner. 



1903 3,017,000 „ 



The author is of opinion that the whole conditions in the North 

 Sea are favourable, for with the increase of material there is a 

 steady increase in yield. 



Another paper of unusual interest is that containing an 

 account of Dr. Hjort's work in the Norwegian sea. Many of the 

 results were known, however, before the International Investiga- 

 tions began. He found three fish-faunas in these northern 

 waters, viz. an arctic fish-fauna on the northern side of the 

 ridge, from the Shetland-Faroe channel to Spitzbergen ; an 

 Atlantic fish-fauna on the southern slope of the great submarine 

 ridge (in the deep basin of the Atlantic) ; whilst a third, allied to 



