EXPLANATION OF PLATE XXIL 

 Fig, 



I, 2. Chloromonas pigra, Ehr. sp., vol. i. p. 401. — Vertical and profile aspects, 

 X 1500 (Stein). 



3-7. Chrysomonas OCHRACEA, Ehr. sp., vol. i. p. 402 (Stein).— 3 and 4, Normal 

 free-swimming animalcules, x 600; 5-7, resting or encysted conditions, 

 accompanied by multiplication by segmentation into two, four, or eight 

 spore-like daughter-cells. 



8, 9. Chrysomonas flavicans, Ehr. sp., vol. i. p. 402 (Stein).— 8, Normal free- 

 swimming animalcule, x 600 ; g, resting or encysted reproductive phase. 

 10. Microglena punctifera, Ehr., vol. i. p. 403, x 600 (Stein). 

 11-13. Nephroselmis olivacea, St., vol. i. p. 405, X 600 (Stein). 

 14-15. Hymenomonas roseola, St., vol. i. p. 408, X 600 (Stein). 



16-18. Cryptomonas OVATA, Ehr., vol. i. p. 404 (Stein). — 16 and 17, Adult animalcules, 

 X 600 ; 1 8, young example. 



19-21. Cryptomonas erosa, Ehr., vol. i. p. 404 (Stein). — 19, Adult animalcule 

 enclosing large ovate germ-mass, x 600; 20, encysted animalcules; 21, 

 example dividing by longitudinal fission. 



22. Stylochrvsalis parasita, St., vol. i. p. 405. — Social group attached to the 



cell-wall of a Etiiioi-ina, one example at a dividing by transverse fission, 

 X 500 (Stein). 



23. DiNOBRYON JUNIPERINUM, Eichw., vol. i. p. 411, dimensions unrecorded 



(Eichwald). 



24-26. Uvella VIRESCENS, Ehr., vol. i. p. 406 (Biitschli). — 24, Socially united cluster 

 of five zooids, x 1200 ; 25, example treated with acetic acid, showing central 

 spheroidal nucleus or endoplast, and two laterally developed pigment-bands ; 

 26, an animalcule dividing by longitudinal fission. 



27. Synura (Rhodessa) Grimselina, Pty. sp., vol. i. p. 412, X 300 (Perty). 



28, 29. Chrysopyxis bipes, St., vol. i. p. 40S (Stein). — 28, Colony fixed to a node of 

 Mougeotia, x 600 ; 29, isolated example showing the two spine-like 

 posterior prolongations of the lorica, by which adhesion to the confervoid 

 algal is secured. 



30-33. Epipyxis UTRICULUS, Ehr., vol. i. p. 409 (Stein). — 30, Social colony, x 600, 

 at a lorica with network-like markings, probably indicating the presence or 

 previous existence of sporular elements ; 31, a more abnormal and closely 

 aggregated colony ; 32, an isolated animalcule with its protective lorica 

 more highly magnified ; 33, an example dividing by oblique fission, as 

 observed by the author. 



34-40. DiNOBRYON sertularia, Ehr., vol. i. p. 409. — 34, Compound detached poly- 

 thecium, x 250; 35, a similar but smaller colonial aggregation, x 1000, 

 at a an animalcule derived by recent fission, attached to the margin of the 

 parent lorica, and constructing for itself by exudation a new protective 

 sheath; 36, an isolated animalcule with its investing lorica^ x 2500; e, 

 coloured eye-like pigment-spot ; am, amylaceous corpuscle ; st, thread-like 

 contractile pedicle or footstalk; «, nucleus or endoplast; cv, contractile 

 vesicle ; 37, example dividing by transverse fission (Biitschli) ; 38, encysted 

 example (Biitschli) ; 39 and 40, examples of encystment, after Stein. 



41. DiNOBRYON STIPITATUM, St., vol. i. p. 410, X 500 (Stein). 



