17S 



p. J. kScourfielp ox entomostraca. 



WANSTEAD PARK ENTOMOSTRACA. 



Diagram showing the Seasonal Distribution of the Cladocera. 



(1) Total number of species — Upper curve. 



(2) Number of species from " Perch Pond" only — Middle curve. 



(3) Males and " ephippial " females — Lower curve. 



? (Averages taken both for numbers of species and for dates.) 



