216 



SCIENCE 



[N. S. Vol. LII. No. 1340 



finding the missing' link in tlie chain, the 

 actual spawning fresh-water eel in the inter- 

 mediate waters somewhere above the abysses 

 of the open ocean. 



Again, take the ease of an interesting 

 oceanographic observation which, if estab- 

 lished, may be foimd to explain the variations 

 in time and amount of important fisheries. 

 Otto Pettersson in 1910 discovered by his 

 observations in the Gullmar Fjord the pres- 

 ence of periodic submarine waves of deeper 

 Salter water in the Kattegat and the fjords of 

 the west coast of Sweden, which draw in with 

 them from the Jutland banks vast shoals of 

 the herrings which congregate there in autumn. 

 The deeper layer consists of " bankwater " of 

 salinity 32 to 34 per thousand, and as this 

 rolls in along the bottom as a series of huge 

 undulations it forces out the overlying fresher 

 water, and so the herrings living in the bank- 

 water outside are sucked into the Kattegat and 

 neighboring fjords and give rise to important 

 local fisheries. Pettersson connects the crests 

 of the submarine waves with the phases of the 

 moon. Two great waves of Salter water which 

 reached up to the surface took place in Novem- 

 ber, 1910, one near the time of full moon and 

 the other about new moon, and the latter 

 was at the time when the shoals of herring ap- 

 peared inshore and provided a profitable fish- 

 ery. The coincidence of the oceanic phe- 

 nomena with the lunar phases is not, however, 

 very exact, and doubts have been expressed as 

 to the connection; but if established, and even 

 if found to be due not to the moon but to preva- 

 lent winds or the influence of ocean currents, 

 this would be a case of the migration of fishes 

 depending upon mechanical causes, while in 

 other cases it is known that migrations are 

 due to spawning needs or for the purpose of 

 feeding, as in the case of the cod and the 

 herring in the west and north of IsTorway and 

 in the Barents Sea. 



William A. Herdman 

 University of Liverpool 



JOHN SAHLBERG 



John Eeenhold Sahlberg passed away on 

 the eighth of May, 1920, in Helsingfors, Fin- 



land, seventy-five years of age, having been 

 bom in Helsingfors, June, 1845. 



Descriptive entomology has lost one of its 

 prominent men; entomological societies — espe- 

 cially the famous Societas pro Fauna and 

 Flora Fennica — an enthusiastic member and 

 officer ; the University of Helsingfors a learned 

 teacher, who knew how to guide his pupils to 

 the very source of biological knowledge — na- 

 ture herself. 



John Sahlberg was an unwearied and highly 

 experienced collector, famous all over Europe, 

 who up to his old age, undertook extensive and 

 strenuous excursions throughout all parts of 

 his native country. He also collected in many 

 other countries of the old world, traveling 

 through the northern parts of Scandinavia and 

 Siberia, and staying in the Caucasus, Turke- 

 stan, Greece and Italy. Three times during 

 the years 1895 and 1904 he visited Asia Minor, 

 Palestine and Egypt. Although thoroughly 

 familiar with all branches of entomology, it 

 was the Cicadarise and the Coleoptera which 

 attracted his especial attention, and to these 

 groups he devoted much study. 



Among the many publications of John Sahl- 

 berg the following may be mentioned : 

 1871 : Ofversigt of Finlands och den Skandi- 



naviska halfons Cicadariae. 

 1873-89: Enumeratio Coleopterorum Fenniae. 

 1878-80: Bidrag till Kordvestra Sibiriens In- 



sekt Faujia. 

 1900: Catalogus Coleopterorum Fennias Geo- 



graphicus. 

 1912-13 : Coleoptera Mediterranea Orientalia. 

 He has left his entomological collections, 

 which are large and of rare systematic and 

 faunistic value, to the Zoological Museum 

 of Helsingfors. 



John Sahlberg belonged to an old Finnish 

 family which for generations has been con- 

 nected with the learned institutions of their 

 native land. His grandfather (Carl Reinhold 

 S.) was professor in natural history, first at 

 the Abo Academy of Science, later at the Uni- 

 versity of Helsingfors. After extensive travels 

 over all parts of the world, his father (Rein- 

 hold Ferdinand S.) was for a period teacher 

 in zoology at the University of Helsingfors. 



