EXPLANATION OF PLATE XLV. 

 Fig. 



1. Stylonychia mytilus, Ehr., vol. ii. p. 790. — Diagrammatic plan of oral ciliary 



system : ad, adoral cilia or membranette ; pra, prasoral, and en, endoral 

 cilia ; u, undulating membrane ; fr, frontal style (Sterki). 



2. Gastrostyla, sp. (Sterki). — Diagrammatic optic section showing disposition of 



the several ciliary systems ; d, dorsal, and m, marginal setae ; par, paroral 

 cilium ; the other lettering as in the preceding figure. 



3-5. OxYTRICHA PELLIONELLA, MiiU. sp., vol. ii. p. 786. — 3, Ventral aspect, x 400 ; 

 4, diagrammatic longitudinal section : ad, adoral, fr, frontal, v, ventral, a«, 

 anal, and d, dorsal cilia or setae (after Sterki) ; 5, ventral aspect (after Stein). 



6. ACTINOTRICHA SALTANS, Cohn, vol. ii. p. 790, X 360 (Cohn). 



7. OxYTRICHA FALLAX, Stein, vol. ii. p. 787. — Ventral aspect, x 170 (Stein). 



8, 9. OxYTRICHA PLATYSTOMA, Ehr. sp., vol. ii. p. 787. — Ventral and dorsal aspects 

 X 300 (Stein). 

 10-12. HiSTRIO sp. (Sterki). — 10, diagrammatic outline of zooid antecedent to sub- 

 division by transverse fission, showing at .f, and s, the newly-growing 

 ventral ciliary series, at pr^, the second peristomal fringe, and at Wi, 1H2, 

 the new elements of the first and second marginal series ; 1 1 and 12, showing 

 disposition and numerical order of development of the newly developing 

 frontal, ventral, and anal series (after Sterki). 



13, 14. HiSTRlO Steinii, MiiU. sp., vol. ii. p. 789. — 13, Ventral aspect, x 200; 14, 

 example dividing by transverse fission, with at pr, and pr, newly 

 developing secondary and tertiary peristomal ciliary systems (Stein). 



15-17. Stylonychia pustulata, Ehr., vol. ii. p. 791. — 17, Ventral aspect, x 150; 15, 

 zooid disintegrating by diffluence ; 16, encysted animalcule (Stein). 



1 8-2 1 . Stylonychia mytilus, Ehr., vol. ii. p. 790. — 18 and 1 9, ventral and lateral aspects, 

 X 150; 20, zooid preparing to divide by transverse fission, the rudimentary 

 second peristomal fringe pr„ being already developed ; 21, variety having 

 the frontal, ventral, and anal styles and setae distinctly fimbriated (Stein). 

 22. Stylonychia fissiseta, C. & L., vol. ii. p. 791. — Ventral aspect, x 300 

 (Claparede & Lachmann). 



23, 24. ASPIDISCA lyncaster. Stein, vol. ii. p. 793-— 23j Ventral and, 24, dorsal aspects, 

 X 250 (Stein). 



25-29. ASPIDISCA COSTATA, Duj. sp., vol. ii. p. 794. — 25 and 26, ventral and dorsal 

 aspects, X 300 (Stein) ; 27-29, developmental phases as observed by the 

 author and described at p. 794. 

 30. Glaucoma margaritaceum, Ehr. sp., vol. ii. p. 796, x 150 (Clap. & Lach.) 



31-33. ASPIDISCA TURRITA, C. & L., vol. ii. p. 793.— Ventral, dorsal, and lateral aspects, 

 X 209 (Stein). 



34-36. Uronychia TRANSFUGA, Miill. sp., vol. ii. p. 797-— 34 and 35, Dorsal and ventral 

 aspects ; 36, example with fimbriated anal uncini, x 250 (Stein). 

 37. Microthorax SULCATUS, Eng.,voL ii. p. 796, x 220 (Engelmann). 



38-40. Glaucoma scintillans, Ehr., vol. ii. p. 795-— 38 and 39, Ventral aspect, with at 

 39, vibratile membrane extended, x 150; 40, encysted zooid dividing by 

 oblique fission (Stein). 



