PLATE L. 



Illustrating the more important modifications of the nucleus or endoplast and nucleolus or 

 endoplastule as developed among the Infusoria. 



EXPLANATION. 

 FIG. 



1. Simple spheroidal nucleus or endoplast, with enclosed nucleolus or endoplastule, of 



a collared monad, Codostga, the same type being distinctive of the majority 

 of the Flagellata. 



2. A single germinal fragment or spore, with contained endoplast and endoplastule, 



of Dictyocysta cassis, x 1000 (Haeckel). 

 3-5. Modifications of the endoplast of Euglena viridis. 3, representing the normal 



form ; 4 and 5, progressive phases resulting in the subdivision of its entire 



mass into sporular elements x 600 (Stein). 

 - 6. Fusiform endoplast, with centrally enclosed endoplastule, of Chilodon cuculhtllus, 



X 480 (Wrzesniowski). 

 7-9. Various modifications of the endoplast of Leptodiscus medusoides (Hertwig). 



10. Ovate endoplast having a reticulate granular consistence, with laterally attached 



endoplastule, of A cineta foetida, x 1280 (Maupas). 



1 1. Subspheroidal endoplast, with numerous enclosed endoplastules, of A cineta Jolyi, 



x 900 (Maupas). 



12. Spheroidal granular endoplast of Rhizopod Pelomyxa villosa, x 1000 (Leidy). 



13. Twin endoplasts, with connecting cord or funiculus, of Litonotus fasciola, x 480 



(Wrezsniowski). 



14. Endoplastic system of Loxodes rostrum, consisting of numerous spheroidal endo- 



plasts with both enclosed and externally developed endoplastules connected 

 together by a thread-like funiculus. In some instances, a a, the external 

 endoplastules are attached to the funiculus, x 600, and treated with acetic 

 acid and iodine (Wrzesniowski). 



15. Twin endoplasts with connecting funiculus vi Litonotus diaphanus after treatment 



with acetic acid and iodine, x 600 (Wrzesniowski). 



1 6. Endoplast of Chilodon cucullulhis with both an internally developed and laterally 



attached endoplastule, x 400 (Wrzesniowski). 



17. Twin endoplasts, with laterally attached endoplastules, of Stichotricha aculeata, 



X 600, + acetic acid (Wrzesniowski). 



1 8. Endoplastule of Pleuronema chrysalis after treatment with acetic acid (Biitschli). 

 19, 20. Modifications of the endoplast of Nyctotherus cordiformis. 19, normal form, 



with laterally attached endoplastule ; 20, endoplast become greatly enlarged 

 and metamorphosed into an elaborately convoluted coil (Stein). 



21. Band-like endoplast with a, investing membrane and b, b, contained endoplas- 

 tules of Vorticella microstoma, x 450 (Stein). 



22, 23. Band-like endoplasts of Carchesium polypinum, subsequent to conjugation ; at 

 22, earlier phase with numerous enclosed endoplastules ; at 23, more 

 advanced stage in which the internal substance has become separated into 

 as many as ten germinal masses which are held together only by the delicate 

 bounding membrane of the originally continuous and homogeneous endo- 

 plast, x looo (Greef). 



