444 POLYPI. CILIATI. 



ORDER V POLYPI CILIATI. 



Mouth furnished with ciliated and gyratory organs, which agi- 

 tate the water, but which do not seize the food. 



The Ciliated Polypi are so small that Muller places them in a division of the In- 

 fusory animals ; but, from having a distinct mouth, Lamarck arranges them as the 

 lowest order of the class Polypi, approximating them in the descending or ascending 

 series to these minute animals. Lamarck besides remarks, that they are higher in 

 organization than the Infusoria, properly so called, from having a distinct and ter- 

 minal mouth ; by moving cirri or ciliated and rotatory organs accompanying this 

 mouth ; by the analogy of their general form ; and by their forming in some cases, 

 as the greater part of the Vorticellae, compound animals. The ciliated polypi live in 

 fresh and stagnant waters, or in sea water mixed with that of rivers ; and many of 

 them possess the faculty of retaining vitality though dried for years, and of recover- 

 ing when placed again in water. Lamarck divides the Ciliated Polypi into two sec- 

 tions, the Rotatory and the Vibratile. 



SECTION I. ROTIFERI. 



With one or many organs in a circular form, ciliated and rota- 

 tory, at the opening of the mouth. 



The Rotiferi are so called from many of them having at the opening of the mouth 

 a pair of dentated wheels which they turn rapidly. These wheels are said to be 

 composed of a plicated circular cord which by its undulations forms a number of pro- 

 jecting and sharp angles, resembling ciliform teeth. The mouth in the polypi of 

 this section is large, campanulate or infundibuliform, and very contractile. 



Gen. 1. TUBICOLARIA, Lam. 



Body contractile, oblong, contained in a tube fixed on aquatic 

 bodies ; mouth terminal, infundibuliform, furnished with a 

 retractile, ciliated, and rotatory organ. 



T. quadriloba, Lam. Tube reddish ; rotatory organ quadrilobed ; 

 lobes unequal. Inhabits fresh waters on the roots of Ranunculus 

 aquatilis. Lam. ii. 53. 



T. alba, Lam. Tube white ; rotatory organs inclined laterally, sub- 

 sinuous. Inhabits fresh waters. Lam. ii. 53. 



Gen. 2. VORTICELLA, Lam. 



Body naked, pedunculated, contractile, fixed spontaneously or 

 constantly by its base, and with the superior extremity infla- 

 ted and terminated by a large mouth furnished with rotatory 

 ciliae. 



The Vorticellae resemble the Hydrae ; but in place of having tentacula round 

 their mouth disposed in rays, and moving slowly, they have cilias, or two tufts op- 

 posed, which have a rotatory oscillation, executed with surprising quickness. They 

 are very minute, and found in stagnant and slow running waters on the stems of 

 aquatic plants. They multiply by natural splittings or sections, of which each forms 

 a new animal. Lamarck divides the genus into Simple Vorticellae, or those which 

 are fixed spontaneously or temporarily ; and Compound Vorticellae, where the pe- 

 duncle is branched and constantly fixed. 



* Simple. 



V. stentorea, Lam. Elongated, tubiform, with a tail ; anterior limb 

 ciliated. Inhabits stagnant waters. Lam. ii. 47- 

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