پرم لال اونیال - Dept. of Botany, Univ. of Delhi, Delhi-۱۱۰۰۰۷, India
سعید شیرزادیان - Dept. of Botany, Plant Petsts & Diseases Res. Inst., P. O. Box ۱۴۵۴, Tehran ۱۹۳۹۵, Iran

The meiotic chromosomes of ۱۰ species (Pohlia elongata, Anomobryum cymbifolium, Brachymenium acuminatum, B. ochianum, B. sikkimense, Bryum cellulare, B. pseudotriquetrum, B. apiculatum, B. capillare and B. atrovirense), in four genera of the family Bryaceae of acrocarpous mosses are studied with special emphasis on their evolution, polyploidy and cytological features with reference to interrelationship among the included genera and species. The occurrence of the heteromorphic bivalent in some taxa and its significance is also discussed. Polyploidy has played an important role in the evolution and speciation of the taxa in the family  and  seems to be an advantage for colonising/surviving in diverse climatic and habitat conditions. 

Cytotaxonomy, moss, Bryaceae, West Himalaya, India