330 



FAMILY: TRYPANOSOMIDiE 



blepharoplast becomes transversely elongated, narrowed at its centre, 

 and finally divided into two parts, the axoneme remaining attached to 

 one half, Coincidently with this the parabasal, if a rounded body, also 

 becomes transversely elongated, constricted, and divided into two, and 

 finally two kinetoplasts are produced, each constituted as the original one. 

 In flagellates like Herptotnonas muscarum, the kinetoplast is an elongated 

 structure with the blepharoplast at its anterior end and the parabasal 

 at its centre. The blepharoplast first divides, and the two halves separate 

 (Pig. 158). The parabasal becomes dumb-bell shaped and also divides. 

 At a certain stage of the process the dividing kinetoplast is in the form 

 of a Y, wdth a blepharoplast at the end of each of the two anteriorly 



Fig. 157. — Kinetoplasts and Attached Axonemes of Degenerate Trypanosoma 

 rhodesiense, as seen in Dried Films stained by Leishman Stain. (After 

 Wenyon, 1913.) 



1. Blepharoplast united to parabasal; the part of the axoneme which borders the membrane 



appears thicker than the intracytoplasmic portion, owing to a sheath of cytoplasm. 



2. Early division with dividing blepharoplast. 



3. Division of blepharoplast and parabasal. 



4. Completed division of parabasal and blepharoplast and outgrowth of new axoneme. 

 .5 and (3. New axonemes forming before division of parabasal is complete. 



directed limbs. The various stages of this division process give the 

 impression that the blepharoplast is leading the way in division, and it 

 appears as if the stress exerted by the separating daughter blepharoplasts 

 causes the parabasal and the entire kinetoplast to divide. The writer 

 (1913a) compared this division with that of the nucleus of Cercomonas 

 longicauda, which in the resting condition is composed of a spherical 

 nuclear membrane with large central karyosome. The anterior part 

 of the membrane is really cone-shaped, and at the apex of the cone is 

 the blepharoplast, from which two flagella arise. In nuclear division 

 the blepharoplast first divides. As the two halves separate a spindle 



