FAUNA OF THE CRESS AND GADE. 



209 



Every specimen examined exhibited very similar movements. 

 The long foot was often extended so as to allow seven joints to 

 be counted with ease, and occasionally eight joints were readily 

 distinguished. After remaining for some time in an extended 

 form and anchored to the slide, the Eotifer would retract its 

 anterior parts, display its powerful wheels and stout column, 

 and swim rapidly through the water. When travelling in leech- 



Fig. 4. 



Fig. 5. 



Fig. 6. 



like manner, R. macrurus often showed, what was very rarely 

 shown by R. vulgaris, a lateral view of the hinder part of its foot. 

 8. Rattulus rattus, Miiller. — From only a few pools have I 

 succeeded in obtaining specimens of this Eotifer. A few were 

 taken from Parsonage Farm Pool, Abbots Langley, on March 

 24th, 1913. One was carefully examined as it swam about 

 rather rapidly and gracefully, turning itself about its long axis, 

 and swaying its foot to and fro. It was brought to rest by 

 means of a few spots of Rousselet's narcotizing solution, and 



