2(>0 DESCRIPTION OF [Polygastrica. 



the frontal margin more expanded. Found upon lemna, 

 rarely, with the former species. Length of body 1 -430th to 

 1 -210th; stalk three to four times that length. 



397. VORTICELLA microstoma. The small-mouthed 

 Vorticella has an ovate body, attenuated at both ends, and 

 having the frontal margin narrow, not expanded. The 

 body, during contraction, is annulated ; its colour whitish- 

 grey. The mouth, stomach, reception of coloured food, 

 male glands, ova, and long muscle of the stalk, have all 

 been observed in this species, as also spontaneous lon- 

 gitudinal and transverse self- division, arid the growth of 

 gemmae. Ehrenberg counted from twenty to twenty-four 

 cilii in the frontal wreath. Found in stagnant water. 

 Length of body 1 -2300th to l-240th; length of stalk 

 six times that of the body. 



398. VORTICELLA campanula {Vorticella lunaris, M.) 

 The great Vorticella has an hemispherical bell- shaped 

 body, with the frontal margin broad and truncated ; not 

 expanded. Colour whitish-brown; (ring, none). This 

 species forms a thick blueish matter upon water-plants, 

 and the single animalcules are discoverable with the naked 

 eye. Size 1-1 20th ; stalk seven times longer than the body. 



399. VORTICELLA hamata. The fish-hook Vorticella 

 has a small ovate hyaline body, attenuated at both ends ; 

 the pedicle is obliquely attached to the body, so as to form 

 something of a fish-hook appearance. Length of body 

 1-5 70th. 



400. VORTICELLA chlorostigma ( Vorticella fisciculata, M.) 

 The green Vorticella has a green, ovate, conical and cam- 

 pan ulate body, which is annulated (wrinkled). The frontal 

 margin is expanded ; the cilii, contractile bladder, and green 



