21 



Vorticella Linnaeus. 

 Of this genus eight distinct species were found, l)ut many forms 

 were found that did not agree with the descriptions given of any former 

 species, yet they differed from the known species in such a manner that 

 it seems better to keep them for further study. 



Vorticella nehulifera O. F. Müll 



Body of medium size, length 70 — 90 /<, breadth 34—44 (.i. 



The specimens were typical or varied so little from it that they are 

 included here. Surface of the body smooth. Specimens are either 

 colourless or coloured green with Zoochlorellae. 



Habitat: Kandel (Nov.), Altwasser Breisach (Dec), Hochdorfer 

 (Dec). 



Vorticella caìyipanula Ehrbg. 



Body of medium size, length 100 ,i<, breadth 85 //. 



The sjDecimens were typical, opaque, and found in groups. 



Habitat: Lehen (Oct., Nov.), Kandel (Dec), Universitätswiese 

 (Nov.), Hugstettin (Nov.), Zoological Garden (Oct., Jan., Febr.). 



Vorticella citrina Ehrbg. 



Body of medium size, length 88 — 120 jt<, breadth 69 — 115 u. 



Two types of specimens were found which must be placed here. 

 The first type agreed in every way with the descriptions of Vorticella 

 citrina^ except in its smaller size. The second type, obtained in the 

 same locality was much smaller in size varying from 50 — 70 u in length, 

 and had markedly convex sides, but in every other detail agreed with 

 Vorticella citrina. 



Habitat: Ziegelei Herdern (Nov.). 



Vorticella alba Fromm. 



Body small, length 54 — 64 //, breadth of body 27 — 32 a, breadth 

 of peristome 37 — 40 fi. 



The specimens presented considerable difficulty, as they were con- 

 siderably larger than any formerly described. In the specimens the 

 peristome border was not reversed but only thickened, the ciliary disc 

 was elevated in the middle above the peristome border, the body was 

 smooth, and they were always solitary. 



Habitat: Kandel (Nov.), Universitätswiese (Nov., Dec), Deichel- 

 weir (Nov.). 



Vorticella cucullus Fromm. 



Body of medium size, length 85 — 100 /<, anterior breadth 53—60 n. 



Three specimens were found and they were cone shaped with 



