The freshwater medusa Limnocnida and associated plankton in the floodplain of the Ayeyarwaddy River,Myanmar

Freshwater medusae of the genus Limnocnida were found in a shallow lake in the floodplain of the Ayeyarwaddy River. The medusae are described and identified as a small form of L. indica. Single immature specimens were found in two other localities in Myanmar, within the Ayeyarwaddy catchment. These records are an eastward extension of the known range of Limnocnida, and indicate that it is probably widespread in the Ayeyarwaddy catchment. The associated phytoplankton and zooplankton are listed, and the zooplankters are compared to those found with Limnocnida in a floodplain lake of the River Sokoto in West Africa. In both situations there was a marked preponderance of rotifers and cyclopoid copepods. This indicates that Limnocnida influences the zooplankton in a manner similar to that found in various studies on the freshwater medusa Craspedacusta in Europe and North America.     

Symbiotic associations between hermit crabs and bryozoans from the Otago region,southeastern New Zealand

Thirteen species of bryozoans (six cyclostomes and seven cheilostomes) occurring off the Otago Peninsula (southeastern New Zealand) form symbiotic, possibly mutualistic, associations with hermit crabs. For all but one of these bryozoan species, such an association has not been reported previously. At most only 3 of the 13 bryozoans are obligate symbionts of hermit crabs. Associations are apparently initiated when a bryozoan larva settles on a gastropod shell occupied by a juvenile hermit crab and develops to form a colony which encrusts the whole shell and then continues to grow out beyond the shell aperture in the form of a helicospiral tube. The tube-building bryozoan colony grows in step with the crab, and tube development appears to be controlled by crab morphology and activity. Of the six species of hermit crabs found occupying bryozoan tubes, four were regular tube occupants, although they could also be found in other shelter types. Hermit crabs occupying bryozoan tubes very rarely indulged in shell exchanges or shell fights. There appear to be no clear cut pairwise correlations between hermit crab species and tube-forming bryozoan species. The following bryozoan species are described for the first time: Heteropora parapelliculata, Borgiola otagoensis, Disporella gordoni, Osthimosia monilifera and O. socialis.     

鱼蚌混养试验的探讨

本文扼要地阐述了鱼蚌混养试验的方法及其管理要点,对提高水体生产潜力有一定的意义。     

福建福安的淡水水母

本文记述了福建淡水水母一新亚种——福安桃花水母Craspedacusta sowerbyi fuanensis subsp. nov. 文章还将福安标本与各地标本作了比较,并提出讨论。     

粤西森林溪流淡水鱼类区系研究

调查发现，粤西森林溪流淡水鱼类有53种，隶属4目13科37属。鲤形目占66．1％，鲇形目占13．2％，鲈形目占18．9％，合鳃目占1．9％，其中鲤科鱼类占总种类的47．2％；可划分为热带平原、江河平原、上第三纪、北方平原、中印山区5个区系复合体。其区系组成具有5个特点，与区域地质演变密切相关。     

华南淡水鱼类保护对策研究

在调查分析华南淡水鱼类致危原因的基础上，针对濒危现状提出保护水域自然环境、合理捕捞、坚持合理引种、建立自然保护区、开展濒危鱼类生物学研究等5项保护措施。     

韩江淡水鱼类区系

韩江为广东省第二次大河,拥有１０２种淡水鱼类。隶属于１６科,７１属,其中鲤科计５６种,鳅科计７种,平鳍鳅科计８种,即鲤开目鱼类在总体上占有最优的势地位。在鱼类区系的组成来看,韩江鱼类与榕江鱼类,九砻江鱼类十分相似,这与它们其有相似的地理状况的河道,以及冰河期间有过联系有关。这些河系的鱼类在早第三纪开始形成。由南亚与东亚地区的淡水鱼类综合而成：一此属如小条鳅属、沙鳅属、异Ｌｉｅ属、白甲鱼亚属从南亚进     

四种淡水鱼在冻藏过程中蛋白质变性的测定

本文阐述了四种淡水鱼在- 5℃、-12℃及-18℃下冻藏近二个月,测定其冻藏期间鱼肌肉蛋白质变性程度。结果表明,四种鱼蛋白质变性大小顺序为:鳙鱼>鲢鱼>草鱼>鲤鱼。     

北川甘溪观雾山组碳酸盐岩的阴极发光特征和成岩作用

本文根据甘溪泥盆系观雾山组碳酸盐岩的阴极发光特征,应用方解石、白云石阴极发光强度主要受控于侠灭剂Fe~2+含量的原理,结合其它分析资料及野外工作,探讨了白云化作用、胶结作用及新生变形作用,并建立了该地区观雾山组碳酸盐岩的成岩序列。