202 MARINE AND FISHERIES 



5 GEORGE v., A. 1915 



I believe we shall find the flora of Georgian Bay quite as luxuriant as that of 

 Lake Michigan, or Lake Erie, and possibly approaching that of Lake St. Clair, 

 although the conditions are quite dissimilar from those reported by Thompson, 

 Snow, and Pieters. This work is valuable from the purely scientific, as well 

 as from its economic side, because of our lack of knowledge of the distribution 

 of the fresh-water algae of Canada. 



The list of water plants now presented is the result therefore of a few weeks' 

 work at the Biological Station at Go Home Bay on the south east shore of Georgian 

 Bay, during August and September, 191L 



A study of algse is especially important in connection with those waters 

 which are the spawning ground and nurseries of the food fish, of which Lake 

 Huron furnishes so large a supply. The innumerable islands, points and inlets 

 along the east shore of Georgian Bay seem to furnish almost ideal conditions 

 for the development of fish life. If we can show that the microscopic creatures 

 are present which form the first food of the fry, and that for these mmute animals 

 there is an adequate quantity of the still more minute plants on which they feed, 

 — ^we shall have gone far toward furnishing a basis for the expectation that scien- 

 tific methods of conservation and propagation will renew the copious supply 

 of fish for which these waters were once famous. 



The chain of life which begins with the unicellular algse and ends with man, 

 has been often demonstrated. The one-celled plants convert the non-living sub- 

 stances — atmospheric gases and water with its dissolved salts — into the lowest 

 form of living matter. Mingled with these are many forms, so lacking in definite 

 characters that so far it has been found impossible to decide their affinities. They 

 constitute the Protista, possibly neither plant nor animal, but of the common 

 structure from which both branches of life have developed. The quantity of 

 unicellular plants per unit volume of water decides the quantity of the Protozoa, 

 Rotifera and Crustacea which may inhabit the waters. These latter are known to 

 serve as the chief if not the only food of the young and small fish. Favorable 

 conditions of shelter and food are indispensable to the growth and rapid develop- 

 ment of the young food fish. We are therefore quite safe in deciding that a prime 

 biological condition for a plentiful fish fauna is the presence of an abundant growth 

 of microscopic plants. 



The surroundings most favourable for the growth of the more minute algse 

 are quiet waters, sunlight, and a plentiful growth of larger plants such as Chara, 

 Potamogeton, Elodea, Utricularia, and Myriophyllum, as bottom and shore 

 growths. These larger plants serve as shelters and homes for the minute forms, 

 and wherever the former are absent, we cannot expect the latter to be abundant. 



The prevailing westerly winds give such an eroding power to the water washing 

 the islands and eastern shore of Georgian Bay that only in the deeper inlets and 

 sheltered bays and river mouths can we find conditions suitable for shore growths 

 of the larger plants. The steepness of the gradient at which the crystalline rocks 

 forming the shore enter the water, seldom permits of an extended submerged 

 terrace of proper depth for the anchored society of plants. Hence only in a few 

 places, and those more or less remote from the open bay, can we find littoral zones 

 characteristic of such quiet shallow waters as Lake St. Clair. 



