PLATE VIL 



Spirastrella purpurea (Lmk.) Rdl. 

 Anatomy. 



Fig. I. S. E. 1365. Portion of a transverse section (cf. PI. V, fig. 19), combined from a few sections of 



a series; cc. central canal ; e. and exc. excurrent canals ; i. incurrent canals; l.b. 



longitudinal bundies of tylostyles; m. group of mastichorions ; r.b. radial bundies 



of tylostyles; x 50. 

 Muscle-cell; X 400. 



Portion of parenchyma (cf. PI. V; fig. 19); x 400. 

 Portion of parenchyma (cf. PI. V; fig. 19); x 400. 

 Tylostyles imbedded in a darkly stained (haemaet. eos.) substance, probably spongin; 



■ 400. 

 Portion of a bundie of muscle-cells, one of which shows the nucleus ; haemaet. eos.; 



oil-imm. Zeiss, Oc. 4. 



