Studies on the Type of Spawning of the Grass Carp,Ctenopharyngodon idellus Liu Yun,Chen Shu-qun,Wang Yi-xian and Gu Hui-qing The Biological Basis of the Annual Spawning Multiplicity of the Grass Carp(Ctenopharyngodon idellus Cuv.et Val.)under Artificial Cultivation Division of Zoology,Department of Biology,Sun Yet-sen Universitv and Fishculture Farm of Nan-hai County,Guangdong Province A Preliminary Study on the Phenomenon of Spawning Twice a Year in the Grass Carp,Silver Carp and Bighead Under the Condition of Strengthened Cultivation Hwang Wen-hao,Li Chang-chum and Gor Shu-min On the Age and Growth of the Chinese Anchovy,Coilia ectenes,from the Yangtze River Yuen Chwan-fuh,Lin King-pang,Liu Jen-hua and Chin An-ling Studies on the Large-scale Algalization of the Late Rice Field by the Inoculation of Nitrogen-fixing Blue-green Algae Section of Experimental Algal Ecology,Fifth Laboratory,Institute of Hydrobiology,Academia Sinica,et al. Studies on Fish Serum Transaminase Activity as a Monitor for Water Pollution Yang Tuan and Guan Lian Studies on the Causative Agent of Hemorrhage of the Grass Carp(Ctenopharyn-godon idellus) Section of Virus Study,Third Laboratory,Institute of Hydrobiology,Academia Sinica Systematic Studies on the Fishes of the Family Homalopteridae of China Ⅰ.Classification of the Fishes of the Subfamily Homalopterinae Chen Ⅰ-yu A New Species of Pseudomurraytrema from Gills of Myxocyprinus asiaticus Chang Chien-ying and Ji Guo-liang A Preliminary Report on Monogenetic Trematodes of Commercial Fishes from the Lake Hong-hu,with Description of Two New Species Chang Chien-ying and Ji Guo-liang