Notes on Cladocera. 79' 



SPECIES 1. 



Plate II. Figs. 1-4. 



Daphnella Exspinosa. sp. nov. 



Length, circ. 0.85. mm. ; height, 0.4 mm. 

 Length of head, 0.25 mm.; of valves, 0.60 mm. 

 Diameter of eye, 0.07 mm. 



Length of head less than half that of the valves. Antennas 

 reaching only aboat two-thirds the length of the valves when 

 bent backward. Post-abdomen without caudal teeth. Eve large. 



The valves are marked only by the ends of the " stutz-balken." 

 Their edges bear numerous small, movable spines (0,0013 mm. 

 long). The shape and general proportions resembles those of D. 

 brachyura (Lieven). There are, however, marked differences in 

 details. 



The indentation between head and body is greater than in D. 

 brachyura. The post-abdomen has no caudal teeth. The termi- 

 nal claws have three teeth and are not serrate. The appendages 

 of the male, in which the vasa deferentia open, do not reach so 

 far as the base of the terminal claws. In D. brachyura they reach 

 beyond the claws. The vas deferens opens, not near the heel of 

 the foot-shaped termination, but below the instep. The anten- 

 nules of the male are longer proportionately. 



Southampton, Mass., 1878. Common. 



Family 2. DapJinidse. 



GENUS 1. 



MoijSTA. Baird, 1850. 



SPECIES 1. 



MoiNA Brachiata. Jurine. 



For synonymy of genus and species, see P. E. Miiller, pp. 132-133. 



Pool beside railroad, near Yahara river, Madison, Wis., July^ 

 1877. Present in immense numbers. 



