LIMNOLOGICAL OBSERVATIONS IN THE UPPER MISSISSIPPI. 407 
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Fig. 19. — Distribution of Leptodora kindtii in Lake Pepin, August 18 to September 10, 1921. (Figures on the chart indicate the average number of individuals, in tens, per 
cubic meter of water. Figures beneath the chart correspond to the serial numbers of stations in the cross sections; upper figures refer to the left side stations.) 
