116 Lake Maxinkuckee, Physical and Biological Survey 



tion or distance, but the suitability of the lake for certain species. 

 Closely neighboring lakes may have a different, and far distant 

 lakes may have a similar, plankton. Shallow lakes, which have 

 more or less warmth and light to much of the bottom, are more 

 heavily populated and have both more diffused plankton and plank- 

 ton scum. A lake resembles an organism in that there must be a 

 certain ratio of surface to volume to produce maximum results. 

 Lake Maxinkuckee differs from the neighboring shallower lakes, 

 such as Bass Lake, Winona Lake, etc., both in the relative quantity 

 of its plankton and in the organisms composing it. The smaller 

 lakes have a much greater quantity of plankton, so that the plank- 

 ton-scum nuisance is much greater in them than at Maxinkuckee. 



The plankton elements are most of them easily carried about 

 from place to place on account of their minuteness and many of 

 them, such as Microcystis, Anabsena, Aphanizomenon, etc., are of 

 world wide distribution. They are therefore likely to thrive in any 

 lake where conditions are favorable. Microcystis, which, after a 

 little practice, can be easily recognized by the naked eye, the 

 vacuolated masses resembling minute smoke rings, is more charac- 

 teristic of warmer, shallower lakes, and Anabsena of deeper, cooler 

 lakes. 



Another point worthy of remark is that of the great abund- 

 ance of diatoms in the plankton during early spring and late au- 

 tumn, and their scarcity or absence during the summer. 



The following are notes concerning a few plankton hauls made 

 in 1908: 



August 25. No wasserbluethe yet, but one small bit of minute 

 stuff which soon disappeared ; much Lyngbya mstuarii; a few col- 

 onies of Microcystis aeruginosa; Anabsena flos-aquss, a few col- 

 onies ; Corethra larvse, common ; some rotifers and entomostraca ; 

 minute white round worms in some of the plankton, one in a dead 

 insect larva ; they may be parasitic. 



August 31. Minute green Vorticellse clustered about a sphere 

 of Anabsena ; Lyngbya SL'stuarii, common ; Microsystis, a few 

 colonies; Anabsena, 2 or 3 colonies; Botryococcus braunii; Vallis- 

 neria flowers ; statoblasts of Plumatella, several ; CEdogonium, 

 one filament; Ostracods, common; broken off Naias, small snails, 

 and Amphipods, abundant ; a few Daphnia ; Copepods, a few, not so 

 common as in night hauls. 



September 7. Lost Lake with a fine scum on top near shore, 

 easily thrown into ripples, composed of fine blue-green grains; 

 Microcystis aeruginosa, common, forming main mass ; Botryoc- 

 occus braunii, frequent; Anabpsna, flos-aqux; Lyngbya xstuarii; 

 a little Daphnia ; Navicula, a few ; Cypris, a few. 



