409 



Anurtea aculatea Ehrenberg. 



Found Nov. 25, 1908, two days after the rain which ended the drouth 

 of that year. It was quite numerous that fall and was present the fol- 

 lowing year until December, but not in such numbers. It was absent 

 entirely in the collections of 1910. 

 Cathypna luua Ehrenberg. 



May 15, 1910. Not common. 

 Diurella tenuior Gosse, 



Spring 1907. Rare. 

 Pedalion mirum Hudson. 



Present in considerable numbers during May and June, 1909. 

 Rotifera tardus Ehrenberg. 



April 15, 1911. 

 Anursea cochlearis Gosse. 



In quantitative collection of April 14, 1910. One specimen; spines well 

 developed. 

 Hydatina senta EhrenT^erg. 



Appeared rarely in spring of 1910. First observed April 14. It did 

 not develop in any quantity until July. On July 15 there were 1,560 per 

 100 liters of water. Aug. 12, this had increased to 1,625. 

 Monostyla lunaris Ehrenberg. 



Appeared April 19, 1910. On that date there were 88 per 100 liters. 

 It reached its maximum development in July with 1,463 per 100 liters. 

 Monostyla cornuta Ehrenberg. 



Aug. 15, 1910. This form may have been counted with preceding but 

 partial re-examination of material did not show this to be true. 

 Diglema forcepata Ehrenberg. 



Occasionally from Feb. 4 to Aug. 15, 1910. 



ANNELIDA. 



Oligochceta — 

 Llmnodrilus sp. 



An oligocha'te worm belonging to the family TubiflcidiB was referred 

 to this genus. Its complete anatomy has not yet been worked out. It 

 occurs in great numbers among the roots and about the root stalks -of 

 Typha. In this pond, this is its exclusive habitat. The alimentary tracts 



