The life cycle of Hebella furax (Cnidaria: Hydrozoa): a link between a lafoeid hydroid and a laodiceid medusa

The adult medusa of a species of the hydroid genus Hebella Allman, 1888 (family Lafoeidae), with a metagenetic life cycle, is described for the first time. Hebella furax Millard, 1957 is epizoic on other hydroids and releases medusae with four radial canals and three marginal bulbs with tentacles. Adult medusae cultured in the laboratory attained 11 mm in diameter, had 8–11 radial canals, and up to 37 marginal tentacles. Cordyli were present between the tentacles, a characteristic feature of the superfamily Laodiceoidea. The pattern of branching of the radial canals indicates that adult medusae of H.furax should be referred to the genus Toxorchis, possibly to T. kellneri Mayer, 1910.     

运用Rasch模型分析生物学作业与教学目标的相符性

Rasch模型作为客观等距量尺的测量工具，用来测量现行的课程作业与教学目标的相符性具有较好的适切性．选取现行课程标准生物学的一个课时内容，将浙江省配套的生物学作业与教学目标进行比对，通过Rasch模型测量生物学作业与教学目标相符性的关系，为教育决策者及命题者提供一种判断作业题目难度恰当与否的方式．     

First clear case of carnivory in marine Copepoda Harpacticoida

Males and females of Ectinosoma carnivora sp. n. from Andros, Bahamas are described. The new species is closely related to E. melaniceps Boeck, 1865 and E. pectinatum Mielke, 1979. A specialized regular slit-shaped glandular pore is described and named the U-pore. Scanning electron microscopy revealed a net of filaments that may cover the whole body of E. carnivora sp. n. It consists of mucus emerging from U-pores. Video investigations show E. carnivora sp. n. and E. melaniceps to be highly mobile and to travel with great velocity in, on and outside the sediment. They exhibit a mode of feeding unreported so far for marine harpacticoid copepods. As observed in laboratory cultures these species are carnivorous and feed on fresh dead ostracods but also on fresh fish meat. When exposed to such food they change their linear movement to what is described here as a helical approach to the food source until contact is established and feeding begins. Carnivory and the ability to locate food sources quickly are believed to be more widespread within the Ectinosomatidae Sars, 1903 and probably are the reason for the great diversity of this family in many different environments.     

当代中国史研究中的口述史问题：学科与方法

在当代中国史研究中，口述史是一个二重概念。它既是一套学术体系或日学科，又是一种方法论。作为学科的口述史与作为方法的口述史在运用方式上有同构性，但在研究理念上则有质的不同。有关回忆录、访谈录等是否算作口述史以及国史研究中的口述史是否可信等问题的争论，实质上是没有区分作为学科的口述史与作为方法的口述史的差别。口述史学是“记忆中的历史”，口述史料是文献资料的补充。     

画龙巧点睛，锦上更添花——评《罗马史纲要》修订版

杨共乐教授的《罗马史纲要》是一部系统的罗马史研究专著，有着较强的原创性，体现了国内罗马史研究的新水平，它的修订出版是我国世界古史学界的一大幸事。     

采用施工图预算控制工程造价的探讨

本文在介绍施工图预算概念及其主要内容的基础上，阐述了采用施工图预算控制工程造价的步骤和特点，并对改革趋势进行了分析。     

瓦氏黄颡头骨的研究(英文)

本文对瓦氏黄颡头骨形态作了详细描述,并对鲶形目续骨的退化和前鳃盖骨功能的转变进行了讨论。通过对鲿科、鲶科、鮡科、胡子鲶科和鲤科共8种鱼类头骨的比较观察,发现鲶类头骨的又一显著特征,即上枕骨上有一对三叉神经叉脊支神经孔。 瓦氏黄颡的头骨由125块(含软骨)组成,其中脑颅37块,咽颅86块(颌弓20,舌弓37,鳃弓31)。其头骨的主要特点可归纳如下: (1)无顶骨、后耳骨和下鳃盖骨; (2)腭骨呈棒状,后端游离,前端与上颌骨关节;上颌骨退化成短棍状以支持触须。 (3)上枕骨具发达的柄状上枕棘及腹脊,以及一对三叉神经叉脊支神经孔。 (4)前囟和后囟均存在,且较宽,表明其在进化上的原始性; (5)由泪骨、侧筛骨、筛骨、鼻骨和前颌骨构成的框架保护其发达的鼻囊; (6)由4对围眶骨和侧筛骨、额骨保护其较发达的眼; (7)前鳃盖骨与舌颌骨、方骨紧密关节,间鳃盖骨紧贴在上舌骨的外面,均参与悬器的形成; (8)鳃弓骨化不全,仅骨化出2枚基鳃骨、2对下鳃骨;相当于基一下鳃骨区域的其余部分终生保留为软骨; (9)具软骨性续骨。     

一种新型感应电动机调速装置：控制模型

新型感应电动机的恒转矩控制装置,经实验和现场运行证明它能用于中、大功率、低同步转速感应电动机拖动风机类和许多非风机类负载系统。本文用定磁场控制原理,论述了感应电动机控制模型和去耦控制方法;最后,提出了整个控制系统线路方案。     

浙江鲤科鱼类咽骨咽齿的研究Ⅱ

本文报导浙江(鱼旁)(鱼皮)亚科鱼类咽骨咽齿的研究结果,根据其形态特点可区分为4种类型。