EXPLANATION OF PLATE XXXV. 

 FIG. 



1-8. VORTICELLA MARINA, Greeff, vol. ii. p. 685. 1-3, Successive phases of longi- 

 tudinal fission resulting in the production of the free-swimming zooids, 

 Figs. 4 and 5 ; 6-8, successive phases illustrative of the conjugation of a 

 free-swimming microzooid with a normal sedentary animalcule, x 200 (Greeff). 



9-24. VORTICELLA MICROSTOMA, Ehr., vol. ii. p. 683. 9-11, Showing production of 

 microzooid by uneven longitudinal fission ; 12 and 13, conjugation of micro- 

 zooid with normal animalcule resulting in the disintegration of the endoplast 

 or nucleus (after Greeff) j 14-16, encysted zooids apparently developing, in 

 the two latter instances, endoparasitic organisms (Stein) ; 17, normal de- 

 tached sedentary animalcule as observed by the author ; 18, encysted zooid ; 

 19, example of production of eight microzooids through repeated fission of 

 primarily segmented moiety (after D'Udekem) ; 20, zooid with two basally 

 attached microzooids ; 21, zooid encysted upon its contracted pedicle (after 

 Stein) ; 22-24, conjugating adult zooids, x 300 (after Claparede & Lachmann). 



25. VORTICELLA ELONGATA, From., vol. ii. p. 686, x 200. 



26. VORTICELLA PATELLINA, Mull, vol. ii. p. 679, x 170. 



27, 28. VORTICELLA MONILATA, Tatem, vol. i. p. 688. At b contracted zooid ; 28, de- 

 tached free-swimming animalcule, x 300. 



29. VORTICELLA CITRINA, Ehr., vol. ii. p. 678, x 150. 



30, 31. CARCHESIUM POLYPINUM, Linn, sp., vol. ii. p. 690. 30, Hinder portion of body 

 that to the left viewed in perspective, that to the right in optic section ; 

 cl, temporarily developed posterior ciliary girdle ; b, obliquely striated band 

 that gives' origin to these cilia ; mm, fibrillae of muscular or myophan layer, 

 c, cuticulum ; ^contracted ectoplasm; 31, obliquely striated band, b of 

 preceding figure, X 2000, showing its granular consistence (after T. W. 

 Engelmann, from a specimen prepared with a one-half per cent, solution of 

 osmic acid). 



32-47. VORTICELLA NEBULIFERA, Ehr., vol. ii. p. 673. 32, Body of adult zooid, showing 

 at m outline of myophan layer continuous with the contractile fibrilla of 

 the pedicle, x 400 ; 33~35, successive phases following upon detachment 

 and encystment resulting in the subdivision of the endoplast or nucleus into 

 nodular fragments ; 39-46, successive phases illustrating the development 

 of a nodular endoplastic fragment through a Strombidium-Xfas, condition 

 (Figs. 38-41) into an ordinarily attached zooid, the example at 40 dividing by 

 transverse fission ; 47, lenticular protective encystment (after Everts). 



48-50. EPISTYLIS FLAVICANS, Ehr., vol. ii. p. 702. 48, Terminal branchlet with two 

 zooids ; v, vestibulum ; ph, pharynx ; ce, oesophagus ; /, food-mass passing 

 through the tubular oesophagus ; /', food-globules discharged into the internal 

 parenchyma or endoplasm ; an, anal aperture, X 200 ; 49, alimentary tract 

 isolated and further enlarged ; or, oral aperture ; b, bulbous enlargement of 

 oesophagus ; s, vestibular seta ; /, flap-like developments of pharyngeal walls ; 

 other lettering as in preceding figure ; 50, basal region of body, showing 

 radiating muscular fibrillae and concentric striae of the cuticulum, x 300 

 (after R. Greeff). 



51. CARCHESIUM POLYPINUM, Linn, sp., vol. ii. p. 690. Diagrammatic outline of 

 peristome and oral system ; p, peristome ; c I, ciliary wreath ; v, vestibulum ; 

 s, vestibular seta ; cv, contractile vesicle ; an, anal aperture (R. Greeff). 



