Knight — 144 — Dictionary 



Synanthesis. — Simultaneous maturation of stamens and stig- 

 mas. 



Synaposematism. — Mullerian mimicry. Adj. Synaposematic. 



Synapsis. — (i) Syndesis; the pairing of homologous chromo- 

 somes of maternal and paternal origin in the prophase of 

 meiosis. (ii) Synizesis; the contraction figure which often 

 appears at this stage in which the chromatin appears to be 

 massed to one side of the nucleus. 



Synaptene. — Zygotene; the stage in the prophase of meiosis 

 during which homologous chromosomes come together in 

 pairs. 



Synchronic Species. — Species which belong to the same 

 time level. 



Synchronous Mitosis. — The occurrence of a number of cell 

 divisions which take place at exactly the same time in a group 

 of neighbouring cells (White). 



Syncryptic. — Resemblance of different species to a common 

 environmental background due to cryptive adaptation. 



Syncytium. — A multi-nucleate protoplasmic agglomeration 

 arising as a result of cell fusion, cf. Coenocyte. 



Syndesis. — Association of homologous chromosomes during 

 meiosis, 



Syndiploidy. — The doubling of the chromosome number 

 through failures in the mitotic spindle. Such a doubling, when 

 it occurs in germinal tissue prior to meiosis may give rise to 

 diploid gametes. 



Syndrome, Genetic. — A genetically controlled group of symp- 

 toms occurring together. 



Syngameon. — A habitually interbreeding community of indi- 

 viduals (LoTSY, 1931). 



Syngamy. — Union of gametes in fertilization. 



Syngenesious. — Having the anthers united (as in Composi- 

 tae). 



Syngenesis. — (i) Sexual reproduction, (ii) The state of 

 having direct or common descent from the same ancestors; 

 blood relationship. 



Syngenetic Relations. — Blood relations; individuals which 

 have direct or common descent from the same ancestors. 



Synheterosis. — The stimulus causing hybrid vigour in diploid 

 organisms (Dodge). 



Synizesis. — See under Synapsis. 



Synkaryon. — A zygote-nucleus ; a nucleus resulting from 

 the conjugation of two nuclei. 



