198 LE NATURALISTE CANADIEN 



fry in that river to be very few. This clearly indicates that the 

 eggs should be cared for. He finds also that in its sea life (the 

 most important growing period, which lasts se ver al years) the 

 shad feeds upon small species of shrimp, similar to but distinct 

 from those (" shrimp " and " red feed ") which form the chief 

 food of the herring. 



Important Médical Substance in Fishes 



Within the past year or so Prof. J. J. R. Macleod and his 

 colleagues in Toronto hâve discovered and investigated the 

 properties of a remarkable substance, which is to be found in 

 the pancréas of animais, and which they hâve named insulin. 

 This substance has the remarkable property of taking away the 

 symptoms of diabètes and may be of enormous value in control- 

 ling this disease. At the station Prof. Macleod this past summer 

 has found this substance in the skate and dogfish, and in a par- 

 ticularly concentrated form in suc fish as the sculpin and monk- 

 fish. Thèse fish, now thrown away, may prove to be of considé- 

 rable importance in this connection. Dr. F. S. Jackson, of 

 Montréal, has co-operated with Prof. Macleod in locating this 

 substance in fishes. 



Experiments on Currents 



The greater currents of the océan hâve long been known, 

 owing to their importance in navigation. The lesser ones, which 

 nevertheless mod'fy climate and affect the distribution of fishes, 

 are still in large part unknown. In 1919 Dr. J. "W. Mavor, of 

 Shenectady, was asked to détermine with drift bottles the cons- 

 tant currents of the Bay of Fundy. This work was done from 

 the stat'on in 1919 and 1920, and has cleared up the matter of 

 the gênerai movement of the water in that bay and in the adja- 

 cent Gulf of Maine. Some of the bottles were caught up in the 

 Gulf Stream and carried to the Azores, the British Isles and to 

 the north of Norway in the Arctic océan. The International 

 Committee on Deep Sea Fisheries Investigations has this year 



