褶纹冠蚌精子发生的研究

光镜和透射电镜研究结果表明：褶纹冠蚌精子发生是非同步的，精子发生经历了一系列重要的形态和结构变化，主要包括：核逐步延长、染色质浓缩、线粒体逐渐发达与融合、胞质消除以及鞭毛的形成。精原细胞胞质中含有许多致密的轴纤丝，它们后来形成鞭毛轴丝。精母细胞质中含有线粒体、中心粒、内质网和电子透明的囊泡。精细胞分化为４个时期。成熟精子属原始类型，由头部、中段和尾部三部分组成。多核结构和细胞间桥自始至终存在于精子

ULTRASTRUCTURAL STUDIES OF SPERMATOGENESIS OF THE FRESH-WATER MUSSEL, CRISTARIS PLICA TA (BIVALVA, UNIONIDAE)

The ultrastructure and development of the male germinal cells of Cristaria plicata were studied with light microscope and transmission electron microscope. The spermatogenesis of Cristaria plicata is asynchronous and contains a series ofconsiderable changes in morphology and structure. These changes include gradual nuclear elongation, chromatin condensation, development and fusion of mitochondria,cytoplasmic sloughing and flagellar formation. The spermatogonium has many dense filaments in the cytoplasm which form the flagellar axoneme in the development. The spermatocyte contains mitochondria, centriole, endoplasmic reticulum and many electron-lucid vesicles in the cytoplasm. The spermatid differentiation can be divided into four stages. The mature sperm is of the primitive type. There are intercellular bridges and multinuclear structure from the early stages until the end of the spermatogenesis.