622 



PROTOZOOLOGY 



V. campanula Ehrenberg (Fig. 281, a-c). Usually in groups; 

 cndoplasm filled with refractile reserve granules; vestibule very 

 large with an outer pharyngeal membrane; 50-157/t by 35-99^; 

 peristome 60-125ju wide; stalk 50-4150/i by 5.6-12;u; fresh water. 



V. convallaria (L.) (Fig. 281, d, e). Resembles the last-named 

 species; but anterior end somewhat narrow; usually without re- 

 fractile granules in endoplasm; 50-95/x by 35-53/i; peristome 55- 

 75^1 wide; stalk 25-460/^ by 4-6. 5^; fresh water. 



V. microstoma Ehrenberg (Fig. 281, /-p). 35-83ju by 22-50^; 

 peristome 12-25/i wide; stalk 20-385/z by 1.5-4^t; common in 

 freshwater infusion. 



V. picta (E.) (Fig. 281, q, r). 41-63^ by 20-37/^; peristome 

 35-50/x; stalk 205-550yii by 4-7m; 2 contractile vacuoles; with 

 refractile granules in stalk; fresh water. 



V. monilata (Tatem) (Fig. 281, s, t). Body with pellicular 

 tubercles; 2 contractile vacuoles; 50-78)U by 35-57/i; peristome 

 35-63jU wide; stalk 50-200ju by 5-6.5 fx; fresh water. 



Genus Carchesium Ehrenberg. Similar to Vorticella; but 

 colonial; myonemes in stalk not continuous, and therefore indi- 

 vidual stalks contract independently; attached to fresh or salt 

 water animals or plants; occasionally colonies up to 4 mm. high. 

 Several species. 



C. polypinum (Linnaeus) (Figs. 34; 282, a). 100-1 25/i long; 

 fresh water. 



Fig. 282. a, Carchesium polypinum, X200 (Stein); b, C. granulatum, 

 X220 (Kellicott); c, Zoothamnium arbuscula, X200 (Stein); d, Z. 

 adamsi, Xl50 (Stokes). 



