Abstract:A number of young fish which appear reversal sides andcolourless on the eye side were found frequently in artificial culture of the flat fish(Pseudopleurcnectes yokohame). The perentage of revrersal individuals in the popula-tion varied from 4% to 79.5% and the percentage of colourless individuals from0.2‰ to 10‰. Twenty one specimens of the reversal young fish were dissected andobserved. and the external and internal characteristics, the cross of optical nervesand the position of the internal organs were especially discribed. The divergencies ofthe individuals of normal and reversal in morphogensis and the growth rate werecompared and tho relationship between the frequency of occurrence and the localtemperature, salinity and the quentity of hormon used in hatchery and cultivationwere analysized as well.

Abstract:This poper presents a genoral summary in many years of re-search petaining to the propagation of white fish(Erythroculter ilishaeformis) inthe Chaohu Lake. It not only accumlates and enriches the relevant material availablebut also verifies emphatically that the specties produces floating eggs and it has a?instinct of upstream breeding migration, thus providing an evidence for the furtheramplying of the fishery resources.

Abstract:The clam (Ruditapes philippinarum) was produced by artificialinduced breading and cultivated in laboratory for the study of its life history Its mor-phological changes at various development stages from fertilized egg to spat (with 7mm, shell length) were observed as well as the yearly change of the spat in naturalsea area. It was further confirmed by observing the morphological characteristics ofspermatizoa and spat that the correction of Ruditapes variegata (Sowerby) which wasmainly cultivated in Fujian province to be Ruditapes philippinarum (Adams Reeve) was valid.

Abstract:1. Since the exploitation of spawning stock of the filefish (Navo-don Septentrionalis Giinther), the variations of its body length, body weight and agecomposition were obvious. The individuals of the stock were big in the years of 1974-1976 and 1981-1983, but small in 1977-1980 and 1984 and smaller in 1985 with carlysexual maturation which showed the declination of the resource. 2. The sex ratio of the fish veried in different seasons. The proportion of malereached to the highest level in spawning period and second in over-wiriter seasonwhile nearly equal to female in feeding season. 3. The spawning ground of filefish covers a wide area from 25°30' N to 30°00'N and 122°00'E to 126°30'E according to the distribution of the spawners, hatchedlarvae and juveniles and catch in spawning season, the area mainly covered from25°45'N to 27°00'N and 122°00'E to 123°30'E. 4. The spawning season of the fish starts from the end of March to the last ten-day of May, the peak period in the middle and last ten days of April. 5. The spewning time of the fish were mainly from 23 p. m. to l1 a. m. nextmorning based on the daily change of the propotions of the ovary stage V_A and V_B. 6. By comparing between the experiment in laboratory the adhesion of the artif-icial inseminated eggs and the natural spawning ground, it showed that gravels, she-lls, seaweeds. sponges and corals were the excellent subetrates for the adhesion ofeggs.

Abstract:The freshwater clam (Corbicula fluminea Muller) is one of theimportant aquatic products in Dian Shan Lake. The age(length)of maturation,repro-ductive cycle and breeding season of the clam were studied in this paper. The breeding season of the clam is from June to September, and some of themcontinue to breed until the end of October.The optimum water temperature for breed-ing is from 25°-28℃. Each individual could ovulate more than once. The age(Iength)of maturation is about 12-13 mm. Since the length of individuals increases, thevolume of the follicles, the age and sperms also increase in size and quantity. For theconservation of the resource, the best season for catch will be October so that thepopulation will maintain in a high level.

Abstract:The ovaries of edible medusa(Rhopilema esculenta) were diassectedand observed by histological sections and scanning of E. M. It was discovered that theovary is fold-type. It's one side connects with gelatinous membrane while the otherside is isolated. Gelatinous membrane is a single layer of ciliated cells, on the outerconsists of spongiocyte. On the side of gelatinous membrane of ovary is one layer ofepithelium which made up of germinal epithelium. The gelatinous membrane andgerminal epithelium connect by colloid fine filaments. Germinal epithelium varies greatyl in spawning season.It accoplishes the func-tion of oogensis at first and gradually dissolves into hyaline little area thereafter. During maturation of the ovary germinal epithelium diffuses locally and the round,oval ova becomes caked. A great deal of ovum discharged in hatches, it is the maintype of ovulation in edible medusa, but diecharge of single ovum also exists.

Abstract:This paper deals with the analysis of feeding hadits and obeservationon the structure in brains of P. extremrs, S. pylzovi, G. eckloni and G. pachycheilus. The correlation between brain structure and feeding habits was discussed. These fourfish belong to bottom feeders with the aid of taste sense. P. extremus and S pylzovifeed on mud and algae mainly with the aid of taste buds in pharynx. The vagal lobesof their brains developed very prominently. G. pachyeilus uses mainly its barbels tosort out aquatic insects, especially crustacean. Its facial lobe and cerabellum of the.brain are largu. The brain of G. ecklcni fits to ils omnivorous feedind habits.

Abstract:In this paper the density of the demersal fish stock was considered as a compoent part of whole marine ecosystem. The data of fish caught were accumu-lated for about two years (23 monthe) and with 1,445 hauls. Materials were system-atically analysed by means of kolmogorov test of goodness fit hypothesis. It was foundthat frequency of distribution was closely related with the theoretical lognormal distri-bution. so we came to the primary conclusion that the index of catch density of thedemersal fish stock followed lognormal distribution. On this basis, we further deducedthat the stock density fillowed lognormal distribution as well. This discovery provideda suitable stochastic model for the study of quantitative distribution of the demersalfishes in the sea area.

Abstract:吕泗渔场的鮟鱇网是张网渔业中使用较普遍的网具,但是鮟鱇网规格受到作业船只长度和作业水深的限制,否则操作困难。同时,由于上、下桁杆笨重,风浪较大时带有一定的危险性。另外现有鮟鱇网一般适应于水深为30米以浅地区作业,难以向深水区发展。如要扩大网具尺寸,提高渔获量,向深水渔场发展,那末务必对现用的鮟鱇网进行改革。

Abstract:鱼类皮肤创伤是渔业生产中常见的一种疾病,并是其他多种疾病的病因。本文供实验的鱼是体长为18—28厘米,体重在90—120克的鳙鱼,共16尾。实验期间水温波动在21—25℃之间。人为创口深0.5毫米,长5毫米。从1985年4月26日暂养至5月8日,在此期间按一定时间分别切取病灶作病理组织切片。

Abstract:生物技术(Biotechnology)既是一门综合性的新工艺,又是一个知识密集的新产业。有人预言,生物技术将成为未来工业结构调整和改革的重要因素之一。 我国是一个十亿人口的大国,农业是国民经济的基础,因此必须加强生物技术在农业应用方面的研究,包括基因重组、细胞融合、固定化酶和固定化细胞等技术,这将大大推动我国整个国民经济的发展。