MORPHOLOGICAL CHANGES IN DEVELOPMENT OF PHARYNGEAL TEETH IN MYLOPHARYNGODON PICEUS

Adult pharyngeal teeth in Mylopharyngodon piceus are molariform. Based on SEM observations ofthe developing teeth, this paper describes the morphological diversification of pharyngeal teeth in M.piceus. The larval and juvenile teeth are changed from conical to adult molariform teeth through sevenstages. Comparisons are made between each stage and corresponding types in some species of differentsubfamilies in Cyprinidae. It is considered that the ontogenetic resemblances of the pharyngeal teehbear relationship to the phylogeny of cyprinids.     

PSEUDOSMITTIA AIZAIENSIS, A NEW SPECIES OF ORTHOCLADIINAE (DIPTERA, CHIRONOMIDAE) FROM HUNAN PROVINCE OF CHINA

Male and female adult midges of Pseudosmittia aizaiensis sp. n. are described and illustrated with figures of morphological characters. The inferior volsella of gonocoxite with large lobes, the long but equal width gonostylus. and the small projection in basal part of outer margin are the characters that may separate this species from others. One larva of this genus is purely aquatic in habitat and is associated with Cricotopus bicinctus, Cardiociadius capucinns and Polypedilum sp. in the same algae debris (Spirogyra sp.) of the Dunghe River. Further, the larva's very short SI and SII bifids. its 5 pairs of lateral teeth on mentum and its absence of premandible brush are the characters that may also separate this species from any known species of this genus.     

APPEARANCE PATTERN OF TOOTH GERMS WITH DEVELOPMENTAL PROCESS IN MYLOPHARYNGODON PICEUS

The pharyngeal dental formula of Mylopharyngodon piceus is 4-5 as a rule, and the dentition isasymmetrical. It is difficult to identify each tooth in the larval dentition. In this paper the appearancepattem of tooth germ with developmental process in this fish is described in detail. The formationpattern of the left dentition is contrasted with that of the right one. In the developmental process,the left pharyngeal dentition lacks teeth at position An3. Thus the left dentition is D-type as designatedby Nakajima(1984), while the right one is A-type.     

The radular morphology of Nassariidae (Gastropoda: Caenogastropoda) from China

The family Nassariidae includes a number of species that are distributed throughout the world. Each species has a characteristic shell shape, tooth shape, and behavior. However, the classification of species in this family of the Rhachiglossa is controversial. We describe the radulae of 22 species from China in detail using optical and scanning electron microscopy. These species are considered to be representatives of two subfamilies, two genera, and 10 subgenera. Our results suggest that the morphology of the central tooth and the pair of lateral teeth and the presence or absence of a pair of intermediate accessory lateral teeth could be used to distinguish among species. We found no support for the subgeneric differentiation of the species. However, the presence or absence of the intermediate lateral accessory plate was characteristic of species divisions. We noted sexual dimorphism in the shape of the teeth in some species, and considerable variability of the shape of teeth within a single species. Based on our results, the genus Nassarius cannot be split into subgenera using radula morphology.     

THE DYNAMIC EFFECTS OF A FINITE DEPTH AMBIENT FLUID ON BOTTOM EDDY

Scaling analysis shows that if o(ε~2, β_1ε, γε) ~o (δ), frontal geostrophic dynamics governs the behav-ior of an isolated bottom eddy in a finite depth ambient fluid; and that the ambient flow induced bybottom eddy migration satisfies quasi-geostrophic dynamics. This two layer model includes the impor-tant processes of advection of bottom eddy due to ambient flow, baroclinic instability, and form dragintroduced by Rossby waves. The numerical results show that the three processes enhance theinstability and alter the migration speed of the bottom eddy, and that the form drag induces asignificant meridional drift of the eddy.     

NEMERTEANS OF ZHOUSHAN ISLANDS, EAST CHINA SEA COAST, CHINA Ⅱ.ENOPLA:DISTROMATORHYNCHOCOELA: MONOSTILIFERA: TETRASTEMMIDAE

A new monostiliferous hoplonemertean, Psummamphiporus microocelli sp. nov., is described. It differs from the single species of genus Psammamphiporus, P. elongatus, in being without a frontal organ and cephalic furrows, the stylet basis being conical rather than cylindrical.     

ON THE BEHAVIORS OF OCEAN BOTTOM EDDY

On the basis of scaling analysis,this paper presents a frontal geostrophic dynamic system which canbe used to describe the dynamics of an isolated bottom eddy and shows that five possible dynamicsubregimes are included in the system.A particle-in-cell method is used to investigate the behavior of the eddy in the two dynamic subregimes,with 1)nonlinear effect(ε)relevant to the sloping bottom-inducedbeta effect(β_1)and 2)seamount-induced beta effect(β_2)dominant.In the dynamic subregime of β_1～ ε～10~(-2)and β_2=0,the eddy can keep as a whole for a long time and migrates for a long distance.Inthe dynamic subregime where the seamount-induced beta effect (β_2～10~(-1))is dominant,the seamounttraps the water particles,causing the eddy to break up into a discrete set of eddies moving around the seamount.     

Design principle for parameters and interferences of tungsten carbide insert interface on roller bits

The lifetime of roll-bits with inserted tooth will be obviously decreased while drilling in strata and the tungsten carbide can be integrally separated from the roll-cone,which will need more trip out time to replace the roller bit.This study provides an entire analysis on stress as well as strength for teeth and tooth holes in loaded conditions.Qualities of tooth drop from matrix within roller bit.The optimized interferences of teeth inserted into the bit can be reasonably obtained by the critical interference derived from some relevant influence factors on the tooth-fixing quality of roller bits.     

On paleoecology of carnivorous dinosaurs ( Tyrannosauridae，Dromaeosauridae) from Late Cretaceous fossil deposits of Amur region，Russian Far East

Present article is on Russian Far East carnivorous dinosaur paleoecology． Described summary is based on detailed study and comparison of isolated shed teeth morphology．     

APPLICATIONS OF ESR DATING AND ~(18)OPALEOTEMPERATURE DATA FOR STUDIES ONQUATERNARY SEA LEVEL CHANGES

Electron Spin Resonance (ESR) dating is a relatively new technique applicable also to the dating of materials from littoral zones and shallow sea regions, such as shells, corals, bones and teeth, foraminifera, diatoms, etc. ESR dating can span the time interval between the older limit of 14C dating and the younger limit of the K-Ar dating, an interval of 103-106 years. Therefore, ESR technique is very suitaHe for the measurement of the age of Quaternary sea-level changes. This paper gives some samples' results by ESR dating from Early Pleistoncene to Holocene.The Quaternary sea-level changes in China were mainly eustatisms that corresponded to the paleotemperature variation. We have just begun study on the 18O Paleotemperature in our continental area. Preliminary results show the temperature curve of the stalagmitic growth in caves corresponds well to the sea - level changes in 76-55×103 years B. P. ESR dating and studies of the 18O Paleotemperature in East China will raise studies on Quaternary sea -     

A NEW SPECIES OF RANINOIDES (CRUSTACEA: DECAPODA: RANINIDAE) FROM OFF THE SOUTHEASTERN COAST OF HAINAN ISLAND AND NANSHA ISLANDS

ＩＮＴＲＯＤＵＣＴＩＯＮＲａｎｉｎｏｉｄｅｓｆｏｕｎｄｂｙＨ .ＭｉｌｎｅＥｄｗａｒｄｓ,1 83 7,ｎｏｗｉｎｃｌｕｄｅｓｓｉｘｓｐｅｃｉｅｓｉｎＩｎｄｏ ＰａｃｉｆｉｃＯｃｅａｎｓ:Ｒ .ｐｅｒｓｏｎａｔｕｓＨｅｎｄｅｒｓｏｎ ,1 888,Ｒ .ｓｅｒａｔｉｆｒｏｎｓＨｅｎｄｅｒｓｏｎ,1 888,Ｒ .ｈｅｎｄｅｒｓｏｎｉＣｈｏｐｒａ,1 93 1 ,Ｒ .ｂａｒｎａｒｄｉｉＳａｋａｉ,1 974 ,Ｒ .ｃｒｏｓｎｉｅｒｉＲｉｂｅｓ,1 989ａｎｄＲ .ｉｎｔｅｒｍｅｄｉｕｓＤａｉｅｔＸｕ,1 993 .ＲｅｃｅｎｔｌｙｒｅｐｏｒｔｅｄＲ .ｐｅｒｓｏ…     

北部湾野生长毛明对虾(Fenneropenaeus penicillatus)体重和形态性状的关系

测量北部湾86尾野生长毛明对虾体长、头胸甲长、胸高、胸宽、第一腹节宽、第一腹节高、第三腹节高、额剑上刺数、额剑下刺数和体重等10个性状,采用逐步回归法分析9个性状和体重的关系。结果表明:体长、头胸甲长、胸高、第一腹节宽、第三腹节高和额剑下刺数6个性状与体重的相关系数达到了极显著水平(P<0.01),在单独的决定系数中:头胸甲长对体重的决定系数(14.44%)最大,共同决定系数中,体长与头胸甲长最大为21.13%。通过分析,建立长毛明对虾的体长、头胸甲长、胸高、第一腹节宽、第三腹节高、额剑下刺数对体重的最优理想回归方程,为长毛明对虾选育种和保种提供理想的测度指标。     

Morphological changes in development of pharyngeal teeth inMylopharyngodon piceus

Adult pharyngeal teeth inMylopharyngodon piceus are molariform. Based on SEM observations of the developing teeth, this paper describes the morphological diversification of pharyngeal teeth inM. piceus. The larval and juvenile teeth are changed from conical to adult molariform teeth through seven stages. Comparisons are made between each stage and corresponding types in some species of different subfamilies in Cyprinidae. It is considered that the ontogenetic resemblances of the pharyngeal teeth bear relationship to the phylogeny of cyprinids. This project was funded by the International Cooperation of Japan—China and the National Natural Science Foundation of China     

Effects of fishes on the growth and survival of Chinese mitten crab,Eriocheir sinensis

This experiment on the effects of fishes (Pelteobagrus fulvidraco, Channa argus, Cyprinus carpio) on growth and survival of juvenile Chinese mitten crab,Eriocheir sinensis was conducted in cages placed in Bao'an Lake. T-tests showed that effects of fishes on the carapace width growth were not significant as compared with the control (no fish). But the effects of these fishes on crab survival were negative. The causes of negative effects of fishes on crab survival were simply discussed on the basis of food habits. This research was financially supported by the Department of Agriculture (96-008-02-03), P. R. China, and Chinese Academy of Sciences (Key Project: KZ951-A1-102).     

A new genus and species of shrimp(Crustacea:Axiidea:Axiidae) from the Caroline Ridge,Northwest Pacific

A new genus and species of axiid shrimp,Carolinaxius kexuae gen.et sp.nov.is described and illustrated based on a single specimen collected from an unnamed seamount in the Caroline Ridge,Northwest Pacific.Although both chelipeds are mis sing,the specimen can be distinguished from other axiid genera by a combination of characteristics:narrowly triangular ro strum;median carina and lateral gastric carina each with one prominent tooth;submedian gastric carinae converging po steriorly,with teeth;cornea weakly pigmented,eyestalk with acute distome sial tooth on dorsal surface;male pleopod 1 two-articled;pleopod 2 with appendix interna and appendix masculina;pleopods 3-5 with appendix interna.The molecular phylogeny suggests the new genus is most closely related to another recently described genus living inside hexactinellid sponges on seamounts in the Indian Ocean,Montanaxius Dworschak,2016.However,it differs from Montanaxius in the shape of the rostrum,the arrangement of teeth on the carapace,and the shape of the eyestalk.Besides,the significant molecular differences support the two belonging to different genera.     

First record of marine crab, Eucrate alcocki Ser6ne, in Ser6ne and Lohavanijaya, 1973 （Crustacea, Decapoda, Brachyura, Euryplacidae） from India

This paper reports the occurrence of a marine brachyuran crab species Eucrate alcocki Serène, in Serène et al., 1973, of the family Euryplacidae Stimpson, 1871, for first time from India, based on a male specimen from Parangipettai fish landing centre in Bay of Bengal, Southeast Coast of India. Although morphologically corresponding with what is currently defined as E. alcocki, the color pattern of the carapace of the present specimen is rather different from that of the Chinese material-only the anterior fifth of the carapace is marked with scattered red spots, the rest of the surface is yellowish, with four unusually shaped red blotches which almost look like Sanskrit characters.     

Report of Pontoniinae Shrimps （Crustacea： Decapoda） Collected by Joint Chinese-German Marine Biology Expeditions to Hainan Island, South China Sea. Ⅲ. PericHmenes

The present paper reports 12 species of genus Periclimenes, subfamily Pontoniinae, collected from Hainan Island, South China Sea, by the Joint Chinese-German Marine Biology Expeditions, in which, Periclimenes consobrinus and P. tenuipes are new records from Chinese waters, and Periclimenes amymone, P. holthuisi, P. soror, and P. toloensis are recorded for the first time from Hainan Island.     

A NEW SPECIES OF THE GENUS NEROCILA （ISOPODA： CYMOTHOIDAE） FROM THE EAST CHINA SEA

A new species of cymothoid Isopeda, Nerocila donghaiensis, collected from the body of a sciaenid fish, Johnius sp., is described in the present paper. The new species can be distinguished from the other species of genus Nerocila by its endoped of uropods with deep notch, sharply serrated on the lateral margin and strongly serrated on the medial margin; antennule with 1 st article swollen; dactyli of pereopods Ⅰ, Ⅱ, Ⅳ, Ⅴ swollen.     

REPORT ON PONTONIINE SHRIMPS（CRUSTACEA：DECAPODA）COLLECTED BY JOINT CHINESE—GERMAN MARINE BIOLOGY EXPEDITIONS TO HAINAN ISLAND,SOUTH CHINA SEA i.ANCHISTUS,CONCHODYTES,CORALLIOCARIS

The present paper reports 7 species of pontoniine shrimps collected from Hainan Island,South China Sea,by the Joint Chinese-German Marine Biology Expeditions,in which,Conchodytes nipponensis(De Haan,1844)and Coralliocaris brevirostris Borradaile,1898 are new records from Chinese waters.     

Genetic improvement on Chinese shrimp （Fenneropenaeus chinensis）： growth and viability performance in F1 hybrids of different populations

Fenneropenaeus chinensis distributed in the Yellow Sea and Bohai Sea of China and the west coast of the Korean Peninsula. Different geographical populations represent potentially different genetic resources. To learn further the characteristics of different geographical population, crosses among two wild and three farmed populations were produced. The two wild populations were from the Yellow Sea and Bohai Sea （WYP）, and the west coast of the Korean Peninsula and coast （WKN）. The three farmed populations included the offspring of first generation of wild shrimp from coast in Korea （FKN）, the Huang Hai （the Yellow Sea in Chinese） No.1 （HH1）, and JK98. The phenotypes growth and survival rates of these populations were compared to confirm the feasibility for crossbreeding. The body length （BL）, carapace length （CL）. carapace width （CW）, height of the second and third abdominal segment （HST）, width of the second and third abdominal segment （WST）, length of the first abdominal segment （LF）, length of the last abdominal segment （LL）, live body weight （BW）, and survival rate were measured, Different combinations were statistically performed with ANOVA and Duncan＇s Multiple Range Test. The results show that the survival rate of JK98（♀）×WKN（♂） was the highest, followed by WYP（♀）×WKN（♂）, FKN（♀）×WYP（♂）, FKN（♀）×HHI（♂） and WYP（♀）×FKN（♂）; the body weight of FKN（♀）×HHI（♂） was the highest, followed by FKN（♀）×WYP（♂）, WYP（♀）×WKN（♂）, WYP（♀）×FKN（♂） and JK98（♀）×WKN（♂）; the total length had the same ranking as the body weight. All growth traits in hybrids JK98（♀）×WKN（♂） were the lowest among all combinations. F1 hybrids had significant difference （P〈0.05） in BL, CL, HST, LL, and BW; and insignificant difference （P〉0.05） in other growth traits and survival rate. The results of Duncan＇s Multiple Range Test are that BL and CL of J