No. 559] NOTES AND LITERATURE 



447 



In the Bull. Inst. Oceanog., Dr. Fage discusses the attempts to 

 introduce the salmon in the Mediterranean, thus far unsuccessful. 



In several papers in the Anatomischen Anzeiger, E. P. Allis, 

 Jr., describes the blood vessels and other structures of many 

 species of sharks and other fishes. 



In the Proc. 7th Inter nat. Zool. Cong., Professor H. F. Xach- 

 trieb describes the lateral line of the paddlefish. Another paper 

 is in the Journal of Experimental Zoology. 



In the Bulletin of the Bureau of Fisheries, XXXII, for 1912, 

 under the head of "The Age at Maturity of the Pacific Salmon 

 of the Genus Oncorhynchus," Dr. Charles H. Gilbert gives a de- 

 tailed account of his investigations of the scales of the salmon, 

 following a method begun by Johnston in his studies of the sal- 

 mon of Scotland. In this paper he shows that the age of the 

 salmon can be determined by its scales and because the salmon 

 of the Pacific Coast runs periodically, this information thus 

 secured may be of great commercial importance. A few years 

 ago a similar study was undertaken by Professor J. P. McMur- 

 rich. Unfortunately this work, which was otherwise well done, 

 rested on an initial mistake. The red salmon, which was taken 

 by him to be a four-year old, was actually five years of age. 



Summing up, Dr. Gilbert presents the following conclusions: 



1. The sockeye spawn normally either in their fourth or fifth, 

 the king salmon either in their fourth, fifth, sixth or seventh 

 year, the females of both species being preponderatingly four- 

 year fish. 



2. The young of both sockeye and king salmon may migrate 

 seaward shortly after hatching, or may reside in fresh water 

 until their second spring. Those of the first type grow more 

 rapidly than the second, but are subject to greater dangers and 

 develop proportionately fewer adults. 



3. Coho salmon spawn normally only in their third year. The 

 young migrate either as fry or yearlings, but adults are de- 

 veloped almost exclusively from those which migrate as vear- 

 lings. 



•4. Dog salmon mature normally either in their third, fourth 

 or fifth years, the humpback always in their second year. The 

 young of both pass to sea as soon as they are free swimming.. 



5. The term "grilse," as used for Pacific salmon, signifies con- 

 spicuously undersized fish which sparingly accompany the 



