NOTES ON JAPANESE PROTOZOA. 



533 



in Japan. Lake Chuzenji and the region of Kyoto furnished the 



best material. 

 Centropyxis Stein. C. aculeata Stein. 



Found in all localities. Very abundant in Lake Hakone. Great 



variation in size occurs in this species and some very large forms 



were observed. 

 Pixidicula Ehrenberg. P. cymbalum Penard. 



A species rarely observed. Found in material from Lake Hakone. 

 Lecqiiereusia Schlumberger. L. spiralis Ehr. (figs. 1-3) ; L. modesta 



Rhumbler (fig. 4). 



These two species are widely distributed in Japan, the former 



being much more abundant. In the typical L. spiralis the aperture 



is usualy directed obliquely toward one side with a prominent hump 



at the outer base of the neck. In the common form in Japan the 



aperture is directed almost straight forward, in very rare cases there 



being a slight prominence at the base of the neck. Common in 



Lake Hakone. Typical examples of L. modesta were found in 



lakes on Mt. Rokkozan. 



L. epistomiwn Penard, a common species of the high lakes of 



Colorado, was not observed in Japan. 

 Difflugia Ledere. D. pyrif ormis Perty ; D. lobostoma Leidy ; D. 



constricta Leidy ; D. acuminata Ehr. ; D. tuberculata Wallich ; D. 



lebes Penard ; D. bacillariartnn Perty (fig. 5) ; D. elegans Penard 



(fig. 6). 



Of the species of Difflugia in Japan, D. elegans is apparently the 

 most common. It is widely distributed and shows a great range 

 of variation. D. lebes, not uncommon in some of the lakes of 

 Colorado, was observed but once, in material from the bottom of 

 Lake Hakone. 

 Pontigidasia Rhumbler. P. spectabilis Penard. 



But one individual observed. From Lake Hakone. A very typical 

 form. 



