MORPHOLOGY OF A FRESHWATER PERITRICHOUS CILIATE,VORTICELLA CONVALLARIA (PROTOZOA,CILIOPHORA,PERITRICHIDA)

The morphology and infraciliature of Vorticella convallaria,collected from both the freshwater ponds near Harbin and Lalin town in China, was described by living and protargol impregnated specimens. Freshwater Vorticella,zooid in vivo 50-85×40-75μm,stout in shape with a wide highly everted peristomial lip. One contractile vacuole ventrally located at the left ofvestibulum and under peristomial lip ;one macronucleus is intestine like,but rather curved in both end. Its adoral end is trans versely oriented and its abord end extends longitudinally to a recurved extremity,nucleus the“S”shape seen in many species of Vorticella ;and two micronuclei located at both end of macronucleus respectively. The number of transverse striations from the peristomial area to aboral ciliary wreath (ACW) was about 74-78,from ACW to scopula,18-24. With 37-42 longitudinalfibers,cell protargol impregnated is like a lantern. Adstomal end of P3 is rather dispersed than other Vorticella ciliatesπ. Peristomi-al disc fibers (PDF) are oblique radiate assignment,with dichotomous end in each fiber, differingconspicuously from the flower or net-like arrays seen in other species of Vorticella. In conclusion,we consider both of the P3 and PDF as the important taxonomic characters in Vorticella convallaria.