374 CHARLES F. ROUSSELET ON ^OTHOLCA TRIARTHROIDES, ETC. 



B. latissvmus and B. longipes, of Schmarda. The former isi 

 considerably broader than long, and coarsely stippled on dorsal 

 surface ; the second is trapezoidal in shape, the mental edge 

 slightly curved, with small notch in the middle, and the foot 

 opening semicircular ; in all these characters they differ from 

 B. spatiosus. 



I was in doubt at first whether this form should not be called 

 a variety of B. Miilleri, with which structurally it is undoubt- 

 edly more nearly allied than with any other species ; but after 

 comparing it with the mounted specimens in my collection from 

 various localities, I have decided to give it specific rank on 

 account of its striking shape. 



Males were not found in the gathering; summer eggs were 

 carried posteriorly in the usual way, but no resting egg was 

 observed. 



Size of lorica of largest specimens: length yV ^^' (^^6 /x), 

 greatest width posteriorly Jy in. (320 jx), width anteriorly ^ Jo ^" 

 (115 fx). 



Habitat : Devil's Lake, North Dakota, U. S. America. 



Description of Plate. 



Fig. 1. jVotholca triarthroides Skorikow, dorsal view^, x 200. 

 ,, la. Notholca triarthroides Skorikow, side view, x 200. 

 2. Brachionus spatiosus sp. nov., dorsal view, x 105. 

 ,, 2a. Brachionits spatiosus sp. nov., ventral view f x 105. 

 2b. Brachionus spatiosus sp. nov., the occipital spines, x 200- 

 2c. Brachionus spatiosus sp. nov., the pectoral edge, x 210. 

 3. Cathypna hrachydactyla Stenroos, dorsal view, x 290. 

 ,, 3a. Cathypna hrachydactyla Stenroos, longitudinal section, 



X 290. 

 36. Cathypna hrachydactyla Stenroos, transverse section, 



X 290 



Jour /I. Qutkiti JUicroscopiad Club, Her, 2, Vol. XL, No. 70, April 1912. 



