26 G- O. Sars. 



Occurrence. — -Some few specimens of this form were 

 raised by the present author in the year 189] from dried mud 

 taken by Mr. Thesen from a swamp at Knysna, lying at some 

 distance east of the Cape of Good Hope. The same form 

 was subsequently found very abundantly in some samples 

 kindly sent to me by Dr. Purcell, who procured them from 

 some ponds on the Green Point Common, near Capetown, 

 accordingly in the very same place, where B. falcifer 

 occurred. But the samples containing B. lamellatus were 

 taken at rather an earlier period of the season than those 

 containing B. falcifer. This seems indeed to indicate a 

 well-marked periodical occurrence of these 2 species, and 

 similar cases have also been observed with several other 

 Entomostraca, appearing at different times in great numbers 

 in the same locality. 



