as figure 5. ’ 
2. Head of a common form. of ie above species. 
--3..-—s Extreme development of the crest. (dg Ee : 
4, -Embryo illustrating the early development of the helmet. eM 
Daphnia kalbergensis Schoedler. 
5. Typical form, from Lake “Minnetonka. enone 5 
6. A form of the above taken from the same gathering. : x es 
7 
8 
7. Post-abdomen of the above. ‘aerate 
. Extreme development of head resembling D. retrocuroa ‘For 
from same gathering as the above. psa 
9. Daphnia dentifera Forbes. patie from hae =e 
Wyoming.” ” ni ere 
+4 
