条纹斑竹鲨雌性生殖系统的初步研究

条纹斑竹鲨为小型体内受精、卵生种类 ,是闽南近海常见鲨类。其雌鱼仅具右侧卵巢 ,呈葡萄状裸露型 ,怀卵量约二三百个 ,卵细胞不同步发育 ,成熟卵径为20～30mm ,卵中含大量卵黄。条纹斑竹鲨卵壳腺的大小随鱼体的生长而增大 ,达到性成熟时约80mm×50mm。卵经过卵壳腺时受精 ,受精卵外被一厚而坚韧的卵鞘 ,为黄褐色、椭圆四角形     

THE PHOTOGRAPHIC CONSTRUCTION OF TOURIST SPACE IN VICTORIAN AMERICA*

ABSTRACT. Tensions and contradictions surround photographic representations of landscape—and the practices that created those representations—during the medium's so-called golden age in the late nineteenth century. These are examined by focusing on the landscape views of H. H. Bennett, a photographer of considerable renown whose stereographs and oversized panoramas of the Wisconsin Dells transformed a working river into a picturesque landscape. Such a construction of genteel tourist space in Victorian America suggests a post-frontier aesthetic in which nature is valued less as an opportunity for progress or an occasion for terror than as pleasing scenery.