PROTOZOA 



B. Osculosa. 



Central capsule egg-shaped, with a principal aperture at the basal pole of the 

 chief axis. Skeleton siliceous, always extra- 

 capsular. Nucleus dividing late. 



III. Nassellaria. — Capsular membrane simple, 

 a porous area at the oral pole of the chief axis. 

 Nassella, Oortina (Fig. 7), Gornutella. 



IV. Phseodaria. — Capsular membrane double ; 

 at the oral pole of the principal axis an osculum 

 closed by a radially striped lid, with a central 

 opening produced in the shape of a chimney. A 

 collection of pigment bodies (phseodium) in the 

 ealymna. Aulosphcera, Aulactinium (Fig. 8), 

 Cannapilus, Challengeria. 



Class III. Flagellata (Mastigophora). 



Organisms which are unicellular or united into 

 simple cell colonies ; properly standing on the 

 boundary line between the animal and vegetable 

 kingdoms, since some groups are directly con- 

 nected morphologically and physiologically with 

 the lowest plants, others, chiefly by their manner 



of taking nourishment (ingestion of solid food), , ,'"■,■", ° . ^* . ^^ ^ "L ^ * , 



s \ s . . , kel) not quite fully drawn, s. Skeletal 



with animals. Furnished durmg the prmcipal ji^g. j^ 2, 3, 4, principal rays; n, nu- 



part of life with one or more vibratile 



a, cleus ; ot, oil-drops ; jsc, podoconug. 



Fro. 8. 



-Aulactinium actinastnun, after Haeckel. n. Nucleus ; c, ealymna ; 

 Ian, capsular memljrane ; op, operculum ; ph, plieeodium. 



