PLATE 5. 



Binary and multiple fission in Trichomonas muris Hartmann. X 2175. 

 All from Peromyscus maniculatus gamheli Baird except Figures 48, 58-66, 

 which are from Mus. sp. albino. 



FiGUEE 46. Normal trophozoite somewhat rounded up showing numerous 

 karyosomes in the large nucleus, cytoplasmic chromidia along 

 chromatic basal rod, blepharoplast at margin attached to 

 anterior flagella, undulating membrane with chromatic 

 margin and basal rod, much curved axostyle with distal 

 chromatic granules. 



Figure 47. Nucleus greatly enlarged (about 6250 diameters) showing 

 numerous subequal ellipsoidal karyosomes and faint linin 

 network. 



Figure 48. Normal free swimming trophozoite. 



Figure 49. Early prophase, chromatic margin splitting, one side detached 

 from end of chromatic rod; blepharoplast dividing, faint 

 intranuclear chromidial cloud emerging. 



Figure 50. Later prophase. Blepharoplast divided, nuclear chromatin 

 in segmented spiral skein. 



Figure 51. The same, with ten chromomeres in the shortening skein. 



Figure 52. Later stage of the same, with shortening skein and evidences uf 

 paired or split chromosomes emerging. 



Figure 53. Late prophase with five pairs of split chromosomes, a small pair 

 anteriorly located, one large, and three medium-sized pairs. 



Figure 54. Later prophase with five massed chromosomes, the small one 

 anterior. Blepharoplast divided; posterior chromatic ring 

 evident on the axostyle. 



Figure 55. Blepharoplasts diverging with straight taut paradesmose 

 stretched between. Chromosomes showing evidence of 

 longitudinal splitting; small chromosome anterior; motor 

 organelles completely divided, attached to blepharoplasts, 

 two lines of cytoplasmic chromidia. 



Figure 56. Anaphase, chromosomes all divided but small lagging one. 

 Division and migration not synchronous; blepharoplasts in 

 polar position, probably divided into polar centrosomes and 

 lateral basal granules bearing the motor apparatus. 



Figure 57. Late anaphase. Chromosomes migrated to polar position, 

 paradesmose applied to outside of nuclear membrane, axo- 

 style detached. 



Figure 58. Early telophase. Nuclei parting by equatorial constriction, 

 chromosomes connected to blepharoplasts by chromatic pro- 

 longations. 



Figure 59. Telophase. Nuclei separated, chromatin massed in central 

 karyosome; short rhizoplast connecting nucleus and bleph- 

 aroplast, paradesmose fading. 



Figure 60. Axostyle splitting longitudinally. Central karyosome breaking 

 up into a number of smaller ones; paradesmose still present. 



Figure 61. Daughter organelles completed, two cytostomes present; 

 paradesmose still persisting. 



Figure 62. Disintegrative Plasmodium formed by multiple fission in stage 

 of 6-nucleate somatella. Each nucleus with axostyle, and 

 intranuclear chromidial cloud. 



Figure 63. Somatella with five nuclei. 



Figure 64. Same with four nuclei. 



Figure 65. Same with three nuclei. 



Figure 66. Binucleate phase following either binary or multiple fission. 



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