WORMS. INFUSORIA. 82. Vorticella. 219 



75T. Br. uncinutus. Bivalve, with the shell unarmed 

 and rounded at the tip, 1-toothed at the base; tail 

 with 2 bristles. 



Adams Microfc. p. ^67. tab. 27. /. 55. 



In ditch water : shell rounded and capable of being opened at 

 both ends, armed with a hook on the fore-part ; tail coniisting of 

 4 or 5 joints. 



758. Br. mucronatus. Bivalve, with the shell 2- toothed 

 at the top and bottom ; tail with a double spine. 



Mutter Verm. i. i./>. 134. n. 145. 



In stagnant water: shell crystalline, rather oblong, truncate at 

 both ends : tail with moveable tranfparent fpines : rotatory-organ 

 mucronate in the middle. 



759. Br. calydjlurus. Simple, calycled, with the shell 

 crenate behind ; upper-lip of the mouth 4>toothed. 



Baker Microfc. p. 304. tab. 10. /. 4-6. 

 In putrid and fresh waters. 



760. Br. quadridentatus. Shell inflated, 4-toothed at 

 top; rotatory organ double; the base 2-horned ; 

 tail long, ending; in 2 short points. 



Adams and Kccnm. Microfc.p. 569. tf,b. 27. /. 58. 



In stagnant waters moving with great celerity, and often at- 

 taching rtfelf to duckweed by means of its tail : shell very 

 tranfparent, 



761. Br. Patina. Shell orbicular, unarmed, entire, with 

 a double rotatory organ, and short simple tail. 



Vorticella circularis. Shaw A'a.'. Mis. t. 199. 

 In stagnant waters abounding in aquatic plants. 



82. VORTICELLA. 



A. Seated on a pedicel or stem, 



762. V , Polypina. Compound, bell-shaped, with a retor- 

 tile much branched stem. 



Adams Microfc. t. 27. /. 61. Nat. Misc. t. 278. 



In sea water, adhering to Fuci, appearing to the naked eye like 

 a white point, and has a double fpontaneous motion. 



763. V. anaslatica. Compound, bell-shaped, with an 

 oblique mouth, and scaly rigid stem. 



Adams Microfc. p. 397. tab. 21. /. 13-16. 



In frcsli waters, forming a cluster branching out in various di- 

 rections : ovaries ieated on the stems in the form of bulbs, which 

 detach themselves from the steins, and fix themfclves to other 

 substances, producing anew cluster. 



764\ V.pyraria. Compound, branched, with inversely 

 conic naked florets, and 2 double tcmacula. 



Adams Microfc. p. 400. mi. 22. /.. 25. 26. 



In stagnant waters, long, fetaccous, rigid, pellucid at the bafe, 

 truncate at top. with 2 lateral arms each side. 



765. V. opercuiaria. Compound, branched, with oval 

 naked florets closed with a fringed lid. 



Adams Microfc. p. 401. tab. 22. f. 29. 



In stagnant waters : stem much branched, jointed. 



766. V. tuberosa. Stem forked, with turbmate florets, 

 each with 2 or 3 tubercles. 



Baker Microfc. p. 350. tab, 13. /. 10-13. 



