ANTARCTIC ROTIFERA 55 



Order EHIZOTA 

 Family FLOSCULARIAD^E 



Genus Floscularia 

 Floscularia, sp. (Plate XIII., Fig. 15) * 



On January 18, 1909, among weed from a pond between Cape Barne and Cape 

 Royds, a species of Floscularia was found in some abundance. When examined after 

 reaching the hut they were moving languidly and showing an inclination to expand. 

 The long setoe, which exceeded the trunk in length, projected as a long brush. The 

 lobes were not unfolded, and there was little time to wait for it. 



Although there is no hope of identifying the species, a sketch of it in the partly 

 contracted condition is given, in order to complete our records of the rotifera of the 

 region. 



In this state the length, exclusive of the setae, was 284 /j.. The foot is transversely 

 wrinkled in the usual manner, and terminates in a conical portion, tapering to a 

 narrow apex (probably the adhesive disc unattached at the time). 



Neither tube nor eggs were observed. The teeth and the various viscera were 

 seen, but detailed studies under pressure could not be made. 



Order PLOIMA 

 Family HYDATINAD^E 



Genus Hydatina 

 Hydatina senta, Ehr. (Photograph from life. Plate II., Fig. 7) 



No description need be given, as the Antarctic examples appear to be quite typical. 

 The species was identified with certainty by Mr. Rousselet from preserved examples. 

 It was found in great abundance in Coast Lake when it was tow-netted for the first 

 time on January 2, 1909. It might have been found much earlier if the lake had 

 been examined in a suitable manner, as there was some open water from the end of 

 November 1908, and the temperature of the water, as early as December 4, was 

 + 47 Fahr. When the Hydatina was first found the temperature had gone down 

 to +40. On January 18, 1909, the temperature had gone up again to +45, and 

 the Hydatina was much less plentiful. 



Large oval smooth brown eggs were known, which proved to be those of 

 Hydatina. 



Under the influence of Eucaine Hydatina behaved well, retaining the normal form 



* An example having the corona fully expanded has s-ince been found, which allows of its identifi- 

 cation as F. cornuta, Dobie. 



