234 



TROCHELMINTHES 



Fig. 371 



Limnias 



ceratophulU 



(from Siissw. 



F. Deut). 



L. ceratophyUi Schrank (Fig. 371). Tube not annulated; length 

 1 mm.; ventral antennae short: on water plants; abundant. 



L. annulatus Bailey. Tube annulated; body with 5 

 horn-like dorsal processes; length 1 mm. 



3. (EciSTES Ehrenberg. Corona a wide oval; lobes 

 indistinct ; tube irregular or absent ; dorsal antenna minute 

 or absent: 10 species. 



0. crystallinus Ehr. Tube variable, transparent, often 

 covered with dirt; ventral antennae small, wide apart; 

 length .5 mm. 



0. melicerta (Ehr.). Two long dorsal projections just 

 below the corona, sometimes antler-like; tube formed of 

 pellets and very short, or wanting: common. 



4. MEGALOTROCHA Ehrenberg. Colonial and sessile, 

 each colony appearing to the eye as a grayish ball; not 

 tubicolous; corona broad, reniform; antennae inconspicu- 

 ous: 2 species. 



M. alboflavicans* Ehr. (Fig. 372). Four opaque warts 

 in a row just beneath the corona; length 2 mm., of colony 

 5 mm. 



5. LACINTTLARIA Schweigger. Colonial and similar to 

 Megalotrocha but each individual is in a transparent tube: 



1 species. 



L. socialis (Pallas). Length 2 mm., of colony 3 

 mm. : on water plants ; less common than above. 



6. CONOCHILUS Ehrenberg. Free-swimming pelagic 

 colonies, each individual in a transparent tube: 3 

 species. 



C. volvox Ehr. Colony spherical, consisting of 10 

 to 40 individuals arranged radially; ventral antennae 

 separate except at base; length .6 mm., of colony 1 

 mm.: common. 



C. unicornis Rousselet (Fig. 373). Colony irreg- 

 ular, containing few individuals; a single large ventral antenna situated 

 on the corona : common. 



ORDER 2. BDELLOIDA. 



Non-tubicolous rotifers (with a few exceptions) which swim with 

 the corona and creep like a leech by attaching alternately the front and 

 hind ends of the body; body cylindrical, with a cuticula composed of 

 rings which can be telescoped; foot usually ending with 3 toes and with 



* See "The Formation of New Colonies of the Rotifer Megalotrocha alboflavicans 

 Ehr.," by F. M. Surface, Biol. Bull., Vol. 11, p. 182. 



Megalotrocha 



alboflavicans 



(from Siissw. 



F. Deut.). 



Fig. 373 



Conpchilus 



unicornis 



(from Siissw. F. 



Deut.). 



