EXPLANATION OF PLATE XX. (continued). 

 Fig. 

 29-51 Ehr.) containing large central modified endoplasts or germ-spheres (after 



{continued). Stein) ; 40 and 41, similar animalcules giving exit by rupture of their germ- 

 spheres to swarms of minute monadiform germs (Stein) ; 43, an animalcule 

 emerging from a temporary encystment (Stein) ; 43, an example of fission as 

 accomplished during the encysted state (Stein) ; 44-48, various phases of 

 encystment accompanied with the production of internal germ-spheres, 

 (Stein) ; 49 and 50, examples of encystment observed by the author, in which 

 the entire endoplasmic contents have become divided into spheroidal spore- 

 like bodies, at 50 a double sporocyst formed apparently by the conjugation 

 of two animalcules; 51, repent amoebiform germs developed from the 

 preceding sporocysts, x 600. 



52, 53. EUGLENA DESES, Ehr., vol. i. p. 383, X 500. — At 53, a young non-flagellate 

 zooid (Stein). 



54-56. EuGLENA TUBA, Carter, vol. i. p. 385. — 54, Normal free-swimming animalcule, 

 X 300; 55, flask-shaped encystments associated in mucous reticulation; 

 56, a single flask-shaped body, more highly magnified (Carter). 



57. EUGLENA VIRIDIS dividing by longitudinal fission, x 300 (Carter). 



58. EUGLENA ZONALIS, Carter, vol. i. p. 388, x 300 (Carter). 



59. CCELOMONAS GRANDIS, Ehr. sp., vol. i. p. 393, X 400 (Stein). 



60-62. Raphidomonas semen, Ehr. sp., vol. i. p. 392. — At 61, example with hair-like 

 trichocysts extended, x 400 (Stein). 



63. Amblyophis VIRIDIS, Ehr., vol. i. p. 386, X 200 (Ehrenberg). 



64. EUGLENA AGILIS, Carter, vol. i. p. 384. — Encysted animalcule, having by the 



abnormal process of serial subdivision become separated into four lineally 

 disposed, equal-sized segment masses, x 300 (Carter). 



