Horizontal Distribution — Swarms. 



369 



catches were scattered from 15,000 to 50,000. While there is 

 considerable variety in these catches, yet, when the length of 

 time and the number of observations are considered, the extent 

 of variation lends no support to the theory of occurrence in 

 swarms. 



Table XXV. — Diaptomus and Daphnia. — December, 1894 — April, 1895. 

 Expressed in thousands per sq. meter. 



December 3 



December 5 



December 7 . 

 December 19 

 January 1 . . 



January 2 .. 



January 6 .. 



January 9 .. 



January 16 . . 



February 14 



Diapto- 

 mus. 



Daphnia. 



19 



103 



13 



144 



28 



154 



27 



93 



24 



100 



22 



116 



18 



78 



25 



91 



26 



138 



17 



118 



17 



57 



23 



41 



13 



45 



17 



52 



25 



55 



12 



48 



22 



65 



22 



41 



15 



36 



8 



39 



11 



36 



29 



54 



16 



57 



20 



60 



16 



53 



13 



61 



23 



53 



23 



43 



February 15 

 February 19 



February 23 



March 6 



March 7 



March 9 



March 12 .. 



March 16 .. 



March 18 .. 

 March 23 . . 



Diapto- 

 mus. 



17 



32 

 38 

 41 

 35 

 29 

 36 

 43 

 48 

 24 

 29 

 31 

 32 

 51 

 36 

 27 

 28 

 45 

 56 

 27 

 34 

 45 

 33 

 71 

 32 

 34 

 33 

 27 



Daphnia. 



51 



42 

 76 



109 

 83 

 86 

 54 

 60 

 66 

 30 

 41 

 48 

 69 

 45 

 56 

 26 

 28 

 63 

 60 

 39 

 83 



102 

 86 



103 

 69 

 72 

 39 

 40 



The foregoing table shows the numbers of Diaptomus and 

 Daphnia hyalina during the winter of 1894-5. Similar results 

 24 



