Knight — 26 — Dictionary 



Chondriosomal Mantle. — A mass of chondriosomes around 

 a nucleus at mitosis. 



Chondriosomes. — Self-propagating bodies, with low refrac- 

 tion, in the cytoplasm, including mitochondria, Golgi-bodies, 

 chondriospheres, chondrioconts, chondriomites and chondrio- 

 plasts. "Mitochondria or chondriosomes are elements of definite 

 form in the cytoplasm of all cells. They lie freely in the 

 cytoplasm, possess the power of independent movement and 

 may take the form of filaments, of rods, or of granules" 

 (Bourne, 1945). 



Chondriosphere. — A spherical chondriosome, made up of 

 several chondriosomes which have coalesced. 



Choriheterosis. — The stimulus causing heterocaryotic vigour 

 in the fungi (Dodge). 



Chorology. — The geographic study of the distribution of 

 organisms. 



Chromasie. — The augmentation of chromatin (in a nucleus). 



Chromatic Sphere. — A daughter nucleus at telophase in cell 

 division. 



Chromatid. — A half chromosome between early prophase and 

 metaphase of mitosis and between diplotene and second meta- 

 phase in meiosis — after which stages, i.e. during an anaphase, 

 it is known as a daughter chromosome. The separating chromo- 

 somes at the first anaphase are known as daughter bivalents, 

 or, if single chromatids " derived from the division of uni- 

 valents, daughter univalents (McClung; Darlington). 



Chromatid Break. — A break in one of two sister chroma- 

 tids which persists as such. Such breaks may be produced 

 by X-ray treatment. 



Chromatid Bridge. — Chromosome Bridge, q.v. 



Chromatid Interchanges. — These "involve breaks in two 

 (or more) chromatids or in different loci of the same chro- 

 matid, and reunion in new ways" (Lea & Catcheside). 



Chromatid Non-disjunction. — The passing of homologous 

 parts of chromatids to the same pole following crossing-over 

 between homologous differential segments in a multiple inter- 

 change hybrid (E. Sansome; Darlington). 



Chromatid Tie. — The link which exists between two non- 

 crossed-over homologous chromatids through their crossed-over 

 sister chromatids. 



Chromatids, Sister. — Those derived from division of one 

 and the same chromosome, as opposed to non-sister chroma- 

 tids which are derived from partner chromosomes at pachytene 

 (Darlington). 



