PLATE XXXIII. 



EXPLANATION. 

 FIG. 



1-6. GYROCORIS OXYURA, Stein, vol. ii. p. 640. i, Adult, and 2, 3, undeveloped zooids, 

 x 300 (after Tatem) ; 4-6, adult animalcules as delineated by Eberhard. 



7-10. UROCENTRUM TURBO, Miiller sp., vol. ii. p. 641. 7 and 8, Free-swimming and 

 posteriorly adherent zooids, X 300; 9, an example dividing by transverse 

 fission ; 10, a-f, showing consecutive contours exhibited by the contractile 

 vesicle. 



11-13. TELOTROCHIDIUM CRATERIFORME, Mull, sp., vol. ii. p. 643. it, Normal ex- 

 ample, x 200 ; 12, zooid with abruptly truncate posterior border ; 13, 

 example dividing by longitudinal fission. 



14-18. TRICHODINA PEDICULUS, Ehr., vol. ii. p. 646. 14-16, Lateral and ventral aspects 

 x 300 (after Stein) ; 17, denticles of adherent disc (after Quennerstedt) ; 

 1 8, the same structures as interpreted by the author; ex. external, and 

 in. internal elements, x 800. 



19-21. TRICHODINA BALTICA, Quenn., vol. ii. p. 649. 19 and 20, Lateral and ventral 

 views, x 350; 21, denticles of adherent apparatus more highly magnified 

 (Quenn.). 



22. URCEOLARIA MITRA, Stein, vol. ii. p. 650, x 600 (Stein). 



23, 24. CYCLOCH^ETA SPONGILUE, Jackson, vol. ii. p. 650. 23, Adult animalcule in 

 profile view, x 400 ; 24, portion of denticulated ring of acetabulum more 

 highly magnified. 

 25. LICNOPHORA COHNII, Claparede, vol. ii. p. 652, x 400 (Cohn). 



26-28. COZNOMORPHA MEDUSULA, Petty, vol. ii. p. 641, x i jo (Perty). 



29. ASTYLOZOON FALLAX, Eng., vol. ii. p. 654, x 250 (Engelmann). 



30. LICNOPHORA AUERBACHII, Clap., vol. ii. p. 651, x 500 (Cohn). 



31. SCYPHIDIA PHYSARUM, C. & L., vol. ii. p. 658, x 300 (Claparede & Lachmann). 



32. SCYPHIDIA LIMACINA, Lach., vol. ii. p. 658, x 300 (Lachmann). 



33. SCYPHIDIA RUGOSA, Duj., vol. ii. p. 659. Expanded and contracted examples, 



x 280 (Dujardin). 



34, 35. GERDA FIXA, D'Udk., vol. ii. p. 657. 34, Expanded zooid almost completely 

 divided by longitudinal fission ; 35, contracted example, dimensions un- 

 recorded (D'Udekem). 



36-38. GERDA CLANS, C. & L., vol. ii. p. 657. 37, An adherent zooid; 38, a free- 

 swimming example with adventitious posterior ciliary circlet, x 150 (Clap. 

 & Lach.). 



