OBSEEVATIONS ON THE GREGAEINES OP HOLOTHUEIANS. 309 



plasm from tlie interior of the cyst. e. An isolated nucleus from the internal 

 masses of protoplasm. 



Tig. 12.— Spores with four nuclei from another cyst, drawn living, using 

 Zeiss, oc. 2, obj. D. 



Fig. 13. — Spores from another cyst. a. A spore with four nuclei, and b, 

 an undeveloped sporoblast, drawn living, using Zeiss, oc. 2, obj. D. c — h. 

 Picric-osmic-acetic, Kleinenberg's hematoxylin. Zeiss, compens, ocular 4, 

 obj. F, cam. luc. X 730. c—g. Spores with four nuclei, h. An abnormal 

 sporoblast with five nuclei. 



Fig. 14. — Two spores from another cyst after treatment with 10 per cent, 

 sodium carbonate (glycerine preparation). Zeiss, compens ocular 4, obj. F, 

 cam. luc. X 730. 



Fig. 15. — From a series of sections through a cyst. a. The cyst-wall, 

 covered by epithelium, b. A spore with eight sporozoites. Zeiss, compens. 

 ocular 4, cam. Inc., obj. F. x 730. c. Another spore with eight sporozoites. 

 Zeiss, compens. ocular 4, homogen. immers. 2 mm., cam. luc. X 900. d, e,f. 

 Sporozoites from other spores of the same cyst, much enlarged. 



Fig. 16. — From a series of sections through another cyst. a. Spore in 

 longitudinal section, showing six sporozoites. Zeiss, compens. ocular 4, obj. 

 F, cam. luc. X 730. b. Spore in transverse section, showing eight sporo- 

 zoites. c. Another spore in longitudinal section, with five sporozoites. Zeiss, 

 compens. ocular 4, homogen. immers. 2 mm., cam. luc. (with the tube of the 

 microscope drawn out). X 1000. d, e,f. Sporozoites from spores of the same 

 section, much enlarged. 



Fig. 17. — a, b, c, d. Four sporozoites, much enlarged, from the spores of 

 another cyst which was cut into sections. 



Fig. is. — Combined semi-diagrammatic figure of a ripe spore, with eight 

 sporozoites. X about 1150. 



PLATE XXVIII. 



All the figures on this Plate refer to G. holothurise, from Holothuria 

 tubulosa, Naples. 



Fig. 19. — Some blood-vessels from Holothuria tubulosa, with vesicles 

 containing Gregarines. Drawn living. 



Fig. 20. — One of the Gregarines shown in Fig. 19, after fixation with 

 Flemming's fluid and staining with alum carmine. X 210. 



Fig. 21.— From a section through a Gregarine, showing the two nuclei 

 (Kleinenberg's picric, borax carmine, hsematoxylin). Zeiss, compens. ocular 4, 

 obj. D, cam. luc. X 315. 



VOL. XXXIV, PART III. — NEW SEE. X 



