Abstract:Observations and histological studies ou the reproductive cyole of sea cucumber(Stichopus japonicus Selenka) were made in Dalian coast, and the results are asfollows: 1. The bighest value of gonad index, value R and biggest primary branch diameterof gonad are found from July to middle of Angust. The spawning indivaduals in thisperiod account for 85--100% of total spawning indiveduals in a year. 2. As to histology, the development of gonad can be divided into 5 stages: rest,Proliferation, growth, maturation and spawhing periods. The period of tho spawningpeak varies with tbe size of the indivdual and locality. The bigger individual inshallow water shows a tendancy to spawn earlier. 3. From the seasonal varfation of the net weight of digostive tract and ite con-tents, which revealod that the period of asetivation of the sea cuoumber in Dalian coastsbegan from August to October. During aestivation period, its intestine atrophiesextremely and it stops feeding. It will begin moving and feeding by the end of October,or the early November

Abstract:The observations and histological studies on the gonad index of abalone were carriedout. The results are as follows: 1. The peak of gonad index by weight can not correspond with the period of thematuration observed by histology. 2.The development of the spermaries can be divided into five periods: 1) restingperiod, in early October to January of next year; 2) recovery period. in early Februa-ry to May 3) pre-mature period, in June;4) mature period, in early July to earlyAugust; 5) spill sperm period, in lato August to Septembor. 3. The development of ovaries can be also divided into five pcriods: 1) restingperiod, in early October to January of next year; 2) recovery period, in early Februa-ry to April; 3) growth period, in early of May to the middle of July; 4) matureperiod, in the late of July to early of August; 5) spawning period, in the late of Au-gust to September. 4. If ever the ovaries develop into maturation, the biggest oocyte is only 162μ indiameter, most of them are about 110μ and the mature eggs in shape can be hardlyobsarved. 5. The sex of abalone is usually constant. But an individual of hermaphrodite isobserved.

Abstract:The scyphistomae of Rhopilema esculenta were cultivated under different untritional conditions from well-fed to starveling in laboratory. The effects of nutrition on the strobilation of the medusa were observed. It was shown that the strobilation rateand the number of ephyrue formed were closely related to nutrient level of scyphistomaeduring low preconditioned temperature (12--7℃) and folowing the induction of risingtemperature (22±1℃). In the absence of nutriment during either period, the strobila-tion would be inhibited or deferred. The strobilation rate usually reached 100% andcach strobila could produce eight ? nine ephyrae in average under sufficient fecding,but the strobilation rate would fall?nd each strobila could only produce two to threeephyrae in malnutrition. After starved for a long time, the organisms became verysmafl and could not be induced to otrobilate generally. It was observed that variouscolours which appeared in the soyphistomae were related to their different proy.

Abstract:1. One of the major factors which effect the yield of the graclaria. agar is theacid concentration at which in the range of 2 .5--4. 0% the product can be prepared.For reinforcing the strength of the products, the acid concentraction would beadjustcdat 2. 0--2.5%, and for increasing the productivity 4. 0--5. 0% would be selecled. Byballancing the reciprocal aid, 3. 5% is selected suitably. 2. The acidification processing operates under the given acid value duration issimple and the data is reliable as well as the good quality of products in copmaring tothe other methods. It would contribute to commercial scale of agar production. 3. In the extracting procoss the bleaching agent is mixes at first with acid andthen the acidification and bleach action take place at same time. Tt is characterised byrapid reaction speed, faster bleaching with lcss bleaching agents. The processing have been adopted by Lanhai Farm's Agar Laboratory Factory inHaikou and a good production with 21. 6% of average yield and 650 g/em~2 of averagestrength of the agar have been achieved.

Abstract:¹³¹I was added to seawater cultare medium and used to study the uptake of iodineby the brown algae (Laminaria japonica) fronds under laboratory conditions. Thefollowing results were rocorded: 1. Discs punched out of different zones of the frond of the algae were exposed to¹³¹I in the illumination and darkness for various lengths of tim. The experimentshowed that the ¹³¹I uptake value were reduced to the average by 33% in the darkness.It seemed that ¹³¹I uptake by seaweed is most likely the active process. 2. The efficiency of¹³¹I absorption of various parts ¹³¹I for 24 hrsobservation every two hours examined and recorded the ¹³¹I uptake. Two highor valuesoccured from 4: 30 to 6:30 a. m. and from 4: 30 to 6: 30 p. m. The preliminary resultshowed the rhythm of ¹³¹I uptake probably occured. 4. Lead, urea and copper would affect the ¹³¹I uptake which was accelerated by0. 5--2. 0 ppm of Pb, 0 .5--10 ppm of N, and 0. 01--0 .05 ppm of Cu respectivoly,but it was inhibited when the concentration is more than 0. 5 ppm of Cu or 20 ppm ofN. 5. It seemed to be a better method that the frond was cut into small discs in regu-lar order to determine the distribution of ¹³¹I in the fronds. 6. The distributlion of ¹³¹I in the fronds of the algae was observed. The absorbed was transported to the basal part during the first weed. The greatest values of theradioactive iodine in basal part appeared after the 3rd day. 7. The analysis of 99 discs from centre to margin of the fronds revealed that thecontent of ¹³¹I was higher in margin than in the central part. 8. Experimont showod that the redioactivity of the cortex of the stipe and base ofthe algae were richcr than that of the pith. 9. The loss curve of radioaetivity from discs of the seaweed is divided into twophase: an initial rapid lost, roughly 50% of abscrbed.¹³¹I was lost within 2 days; thenthe ¹³¹I lost slower. 10. L. japonica may be used as bioindicators of the radioactive poliution.

Abstract:Silver carp and blg-head carp swim so fast in open waters that it is difficult tocatch thom by means of the traditional trawl net. It is the reason why trawl net hasrarely been used in freshwater fishing. During 1982--1983, a new kind of four panelfrawl net with large-mesh was designed and tested in two large reservoirs in differentseasons. It was proved that the new designed trawl net can be used for catching silvercarp and bighead carp effectively and the fish below the catcheble size, can, escapethrough the meshes. The result indicates thaet the large-mesh trawl net has severaladvantages, such as simpler in net structrre, lighter in weight, lower in cost,increasein catches and easier in operating.

Abstract:This paper presents the cycle of histological changes in the ovary of the icefish(Protosalanx hyalocranius Abbott). Samples were collected from Chongming andJinshan, along the coast of the Dong Hai Sea near Shanghai. The course of ovarian maturation is divided into six stages and a recoveredstage of Ⅵ--Ⅲ. The ovaries devrelop to Stagu I in April-May;Stage Ⅱ in June-Oct.;Stage Ⅲ in early Nov.; Stage Ⅳ in mid-Dec. The mature rish spawn at the end ofDec. and continue to April of the next year. After the fish released the first batch of eggs, the ovaries regenerate into StageⅥ-Ⅲ, which continue to develop rapidly into Stage Ⅳ′About half a month laterthe ovaries develop into stage Ⅴand are ready for a second spawning. The resulte indicate that this species releases at least fwo batches of eggs during itsreproductive period. It is obvious that the fish is a multiple spawning type After thelast-spawning the parent fish die off. The lifespan of icefish is only one year.

Abstract:Fertilized eggs of red spotted grouper,Epinephelus akaara(Temminck ot Schlcgel)were obtained from induced spawning. The development of the eggs and larvae of thisfish were observed and studied in May, 1983 at Yan Tian mariculture ExperimentBasc, Nan Hai Fish. Res. Inst. The egg is pelagic (but the fertilized egg is demersal at the salinity below 27‰and pelagic abovre 29. 5‰), spherical in shape measuring 0 .74±0. 03 mm in diameter.The yolk is colorless, transparent, with a single oil globule, 0. 15±0. 01 mm in diame-ter. The egg develops to 2-cell stage 43 minutes after fertilization at the watertemperature 25. 0℃, salinity 30‰. The first egg hatches about 24 hours after fertiliza-tion at 25. 0--25. 9℃. No melanophores appeared in the periool of the embryonic deve-lopment. The newly hatched larvae measured 1.09--1 .21 mm in total legth. The number of myotomes is 11+14 =25. No pigment cells appeared in the body, but the surface ofthe body as well as the marginal fin and the yolk sac is covered with granules, and thefirst appearce of the melanophores was observed on the dorsal part of the alimentarycanal 15. 5 hours after hatching. The 3 days old larvae attained 2 .47--2. 62 mm in total length. The mouth opens,and the position of anus transfers to the middle part of the body and opens at situationof 10 th myotome, and it was measured 0. 125--1 .36 mm in mouth cleft length. Theyolk is almost obsorbed and oil globule was entirely consumed. In 4.5 days the larvae attained 2.49--2.70 mm in total length and yolk wasentirely obsorbed. In the stage of 6 days, total length of larvae was 2. 85--3. 17 mm.The dorsal fin base appeared just above the 1--8th myotome. The larval development of red spotted grouper is found to be similar in its earlylife history to those of other serranids, such as the brown spotted grouper(Epinephelustauvina Forskal) in Kuwait Waters, White-spotted green grouper (E. amblycephalusBleeker) and green grouper(E. awoara Temminck et Schlegel) in the East ChinaSea.

Abstract:The weight incrcase of "cis-cross" F₁--Cyprinus carpio var. wuyuanensis ♀×C.carpio yuankiang ♂ is fast than parent C. carpio var. wuyuanensis by 30.05-38. 57%, P<0. 01, fast thah perent C. carpio guankiang by 21. 2--23. 2%,P<0. 01. The weight increase of "trans-cross" F₁--C. carpio yuankiang ♀×C. carpio var.wuyuanensis♂ is fast than parent C. carpio Nar. euyuanensis by 14. 33--19.62%,P<0. 01;fast than parent C. carpio yuankiang by 14. 14%, P<0.01. The weight increase of "cis-cross" F₁ is fast than "trans--cross" F₁ by 5. 2--23.8%, P<0.01 or P>0.05. Among the four backcross carps,the backcross carp B₈--C. carpio yuankiang ♀×(C. carpio var. wuyuanensis ♀×C. carpio yuankiang ♂) ♂ is the best. The weightincrsase of backcrossB₃. is fast than "cis--cross" F₁ by 14%, P<0. 01. The weight increase of F₁ is almost the same with that of F₂, P>0. 05. Their dif-ferance is not obvious. The catching rate and survival rate of "cis-cross" F₁, "trans-cross" F₁, backcrossand F₂. are relatively high. "Cis-cross" F₁ and backross carp B₃ are two .fairly good rearing species whichhave higher econolnical bcnefit and are worth while to popularize in fish farming.

Abstract:pectoral fin long, reaching vent;caudal fin shorter than the length of the head; body with 9 dark transverse bands;ventral fin dusky with a bright yellow, broad median stripe;caudal fin with 9--10zigzag bands above. While the present species has 6.3--6.4 (female) or 7.4--7.8(male) in depth, head 4. 3--4.7; pectoral not reaching vent; caudal 1. 2 times longerthan the length of the head; body without clear spots or bands; ventral plain, withouta bright yellow, broad median stripe; caudal without zigzag bands. Holotype no. SN--0431 (male), length without caudal 69 mm., collected fromNanhui, Shanghai, On May 12, 1980. Kept in Dong Hai Fisheries Research Institute. Paratype 5: nos. 60-1637, 60--1638, 60--1779, 43637 43637, length 60--65 mm.from off Zhejiang Province in Feb. 1960. Kept in Dong Hai Fisheries ResoarchInstitute and Shanghai Fisheries College. 2.Acanthogobius luridus Ni et Wu sp. nov.(Figure 2)D. Ⅷ--Ⅸ, Ⅰ--10--11; A. Ⅰ-10;P. 20; V. Ⅰ--5. L1. 34--35, Ltr. 8--10; Predorsal scales 13--16. Gill-rakers 2--3 + 8--9. 4.6--5.8 in Depth, head 3.5--3.8. Snout 3. 1--3.5 in head, eye 5.2--5.5,interorbital 7. 8--9. 1. This new species is allied to the Acanthogobius jacoti (Fowler) recorded fromQingdao, China, but the second dorsal fin of the latter with 15 rays, 28 longitudinalscales, while the present species having 10--11 dorsal rays and 34--35 longitudinalscales. Holotpe: no. SN--1286, length without caudal 61. 8 mm., collected from Yangtzeriver off Baozhen, Chongming, Shanghai, kept in Dong Rai Fisheries Research Insti-tute. Paratype 10: nos. 56--3, 61--2, 61--100, (61) 9977,(61) 0413, 75f--0661, 75f-0733, SN-1289, SN-1294, length 50--63 mm., from Wusong, Jinshan, Chongming,Chuansha, Shanghai, in 1956--1982. Kept in Dong Hai Fisheries Research Instituteand Shanghai Fisheries college.

Abstract:在脊椎动物的所有异配性别中,无论是XY型或ZW型,都发现有H-Y抗原,它在XY型动物精巢或ZW型动物卵巢的分化中起着重要作用。为此,弄清H-Y抗原在鱼类中的表达及其免疫机制就可能成为研究性细胞发生、进化及种族鉴定的理想工具,而且还可期望用于控制鱼类的性腺发育。