14 



COMPARATIVE PHYSIOLOGY, 



of the vacuoles found in any of the organisms thus far consid- 

 ered. It is worthy of note that Amceba may spontaneously 

 assume a spherical form, secrete a structureless covering, and 



Fio. 8. 



»IG. 9. 



Fio. 10. 



Fio. 11. 



Fio. 12. 



Fig. 13. 



Fio. 14. 



i^<? 



FlQ. 15. 



Fig. 16. 



FiQS. 8 to 15, represent eucceBsive pbases in the lif e-histoiy of an Amoeboid organism' 

 kept under constant observation for three days ; Fig. 16 a similar organism en" 

 cysted, which was a few hours later set free by the disintegration or the cyst. 

 (AH the figures are drawn under Zeiss, D. 3.) 



Fig. 8. — The locomotor phase ; the ectoplasm is seen protruding to form a pseudopo- 

 dinm, into which the endoplasm passes. 



Fig. 9. — A stage in the ingestive phase. A vegetable organism,^, is undergoing in- 

 tussusception. 



Fig. 10.— a portion of the creature represented in Fig. 9, after complete ingestion of 

 the food-particle. 



Fig. 11, 12. — Successive stages in the assimilative and excretory processes, , Fig. 12 

 represents the organism some twenty hours later than as seen in Fig. 11. The 

 undigested remnants of the ^ingested organism are represented undergoing ejec- 

 tion (excretion) &tfp, in Fig. 12. 



Figs. 13, 14, 15, represent successive stages in the reproductive process of the same in- 

 dividual, observed two days later. It will be noticed (Fig. 13) that the nucleus di- 

 vides first. 



In the above figures, vc, denotes the contracting vacuole ; nc, the nucleus ; ps, pseu- 

 dopodium ; dt, diatom ; fp, food-particle. 



