Knight — 122 — Dictionary 



Progeny Size. — See Appendix 1. 



Progestin. — A term used to include all the hormones of the 

 corpus luteum governing pregnancy (Mottram, 1944). 



Prolan. — A sex hormone occurring in some mammals during 

 pregnancy (e.g. in urine of pregnant women). 



Proloestrum. — The period of sexual preparation which pre- 

 cedes heat, or oestrum. 



Prometaphase. — The period, in mitosis or meiosis, between 

 the disappearance of the nuclear membrane and the moment 

 when the spindle is fully formed. 



Prometatropy. — Obigatory cross pollination. Adj. Prometa- 

 tropic. 



Promitosis. — A simplified form of mitosis, found in Protista, 

 in which the whole process takes place within the nuclear 

 membrane. 



Pronucleus. — The nucleus of an egg, sperm or pollen-grain. 



Pro-oestrum. — The period of sexual preparation which pre- 

 cedes heat, or oestrum. 



Prophase. — The first stage in mitosis or meiosis. For details 

 see Mitosis and Meiosis. 



Proplastids. — Primordial plastids occurring in meristematic 

 tissue. 



Prostate. — A gland situated around the urethra near the 

 neck of the bladder. The prostatic secretion is added to the 

 semen at the time of ejaculation. 



Protandrous. — With anthers ripening before the stigmas. N. 

 Protandry. 



Protanthesis. — The commencement of flowering in an in- 

 florescence. 



Proteranthy. — The state of bearing flowers before the foliage 

 unfolds. 



Protogene. — Pearson's term for a dominant allele as op- 

 posed to allogene. 



Protogenesis. — Reproduction by budding. 



Protogynous, Proterogynous. — With stigmas ripening (be- 

 coming receptive) before the anthers. N. Protogny, Pro- 

 togyny, Proterogyny. 



Protoplasm. — Living cell substance including the nucleus 

 and cytoplasm. 



Protoplast. — The portion of a cell which is truly living; the 

 protoplasm of one cell. 



Protosome. — Thompson's (1931) term for the physical gene 

 base, which, according to Agol (1931) and Dubinin (1932), 



