PROTOZOA. 



I 59 



FIG. 39. 



FIG. 40. 



FIG. 39. A, Vorticella, a stalked, ciliate infusorian: i, contracted; 2, extended. 

 /, food vacuoles; g, gullet; m, contractile (muscular) fibre; n, nucleus; o, mouth, sur- 

 rounded by a ciliated disc; p.v., pulsating vacuole; s, stalk. B, a colonial type similar 

 to Vorticella. 



FIG. 40. A, Euglena viridis, a flagellate infusorian. i, typical swimming con- 

 dition; 2, somewhat contracted; 3, spherical resting condition; 4, encysted stage in 

 which division has taken place, c, cyst; /, flagellum; n, nucleus; o, mouth; p.v., pul- 

 sating vacuole, sp, pigment spot. B, Podophrya, a stalked infusorian bearing sucking 

 tentacles (f). p, infusorian captured for food; 5, stalk. 



Questions on Figures 39 and 40. Compare the internal structure 

 of Vorticella, Paramecium, and Euglena. What are the principal 

 similarities and differences? Compare all the protozoa figured, as 

 to degree and method of locomotion, method of taking food, and 

 mode of reproduction. Compare these types with those figured in 

 Fig. 7. 



