1052 Wisconsin Academy of Sciences, Arts, and Letters. 
7. Note on Pleuroxus hamulus Birge and Alonella dadayi, 
sp. nov. 
P. hamatus. 
This species was first described by me in 1878. It appears 
that the specific name hamatus was first used by Baird in 1835 
as the specific name for a species of Pleuroxus (See Baird ’50, 
p. 136) which proved to be founded on a male of some other 
species. The name, therefore, cannot be used again for a 
species of Pleuroxus and in place of it I substitute the name 
Pleuroxus hamulatus. The characters of the species remain 
unchanged. 
A. dadayi sp. nov. 
The shape is oval-rotund. The valves are strongly reticulated 
all over; the infero-posterior angle is rounded, with several 
minute teeth. The rostrum is long, pointed, recurved. The 
keel of the labrum is acuminate behind and with one projection 
on the ventral margin. The post-abdomen is short and wide; 
the pre-anal angle strongly marked, as in Chydorus; with numer¬ 
ous small denticles; apex rounded. Claws with one basal spine* 
Male with usual characters. 
The color is yellow to brown, often opaque. The length of the 
female is 0.25—0.3 mm.; male about 0.2 mm. 
This species is identical with Leptorhynchus dentifer Daday. 
The reasons demanding a change of name are given above, p. 
1049. For figures see Daday ? 05, pi. X, figs. 18-23. 
8. List of Southern Species new to the United States. 
In 1903 I visited the southern United States collecting 
Cladocera, chiefly in Louisiana and Texas. The following 
species, new to the United States, appeared in my collections, 
of which I hope to publish later a more complete account. 
