• The Korean Journal of Malacology
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• v.2 no.1
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• pp.30-34
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• 1986

Genetic variations of Semisulcospjra gottschei in Korea were investigated by means of starch gel-electrophoresis. The results are as follows; 1) Eight loci of ${\alpha}$-Gpd, Mdh-2, Pept-1, Pgm-2, Gp-1, Gp-2, Gp-3 and Gp-4 were monomorphic, and 8 loci of Mpi, Mdh-1, Pgi, Got, Pept-2, Pept-3, Pgm-1 and Sdh showed genetic variations. 2) Means of allele per locus ($\bar{A}$) and polymorphism (P) were revealed 0.64 and 0.44, respectively. The value of heterozygosity ($H_G$) showed a little more than heterozygosity $H_D$. ($H_D$=0.09, $H_G$=0.13) 3) Genetic variation appears to be due to loci of Got, Pept, Pgi, and Sdh, all of which of the $H_D$ values are high.

• The Korean Journal of Malacology
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• v.2 no.1
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• pp.26-29
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• 1986

Corbicula fluminea, one of the 2 species in the family Corbiculidae living in the Lake Uiam, was used as an experimental material and the embryonic development and the structure of glochidia of this species were investigated. This freshwater mussels was oviparous, but some ovoviviparous: incubated their youngs in the inner-demibranchs or outer-demibranchs, however, chiefly used the inner-demibranchs as brood-pouch. The average time required from a fertilized egg to two-cell stage, veliger stage, and glochidium was 76 minutes, 3 hours, and 17 hours, respectively, The mean size of glochidium was $168{\mu}m$ in shell height, $195{\mu}m$ in shell lengh, $114{\mu}m$ in hinge legth and the form of glochidium was D-type and had no hooks or hooklets for attaching to fish like Unioidae.

• The Korean Journal of Malacology
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• v.7 no.1
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• pp.49-57
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• 1991

A study on the distribution and community structure of the benthic macroinvertebrates on the intertidal zones of Gapa and Mara islets were carried out from March to June 1991. The macroinvertebrates collected and identified were composed of 7 phyla, 14 classes, 29 orders, 68 families and 132 speies in Gapa islet and of 7 phyla, 12 classes, 23 orders, 49 familis and 90 species in Maara islet. The first and second dominant species and the community dominance indices of the upper tidal zones of Gapa and Mara islets were Nodilittorina exigua, Pollicipes mitella and 79.01, 69.77 respectively. However, the dominant species of the middle and lower intertidal zones of the two islets were not identities and different among the tidal zones.

• The Korean Journal of Malacology
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• v.7 no.1
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• pp.66-75
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• 1991

금강수위에 서식사는 패류의 중금속함량을 알아 보기 위하여 1001년 4월부터 동년 10월사이에 우기를 피하여 금강유역에서 8개 지소를 임으 선택하여 채집한 8종의 부족류 중 비교적 각 지역에서 공통적으로 채집될 수 있었던 말조개와 채첩을 각각 10개체씩 선택하여 패를 아가미, 외투막, 폐각근, 족근 및 내장기관등 각 부위별롸 나누어 Cd, Cu, Pu, Zn의 함량을 원가흡광법으로 분석하여 다음과 같은 결론을 얻었다.1. 각 부위별 중금속 함량을 전체적으로 본 평균값은 Zn을 제외하고는 전체 패류의 내장부위가 모두 다른 어느 부위보다도 매우 높은 함량을 나타냈으며, 그 다음은 지역에 따라 다소의 차이는 있언ㅆ지만 대부분 외투막과 아가미, 족근, 폐각근의 순으로 나타났다.2. 각 패류별 중금속 함량은 역시 Zn만을 제외하고는 상류로부터 하류로 내려감에 따라 중금속 함량이 높아지는 경향을 보였다.3. 여러 금속 중 Zn만이 각 부위별에서 내장부위보다 아가미, 외투막에서 비교적 높은 값을 볼 수 있었으며, 일반적으로 다른 중금속은 하류보다 상류가 그 함량이 적은 경향을 보였으나, Zn만은 상류족에서 비교적 높은 함량을 보였고, 지역에 따라 그 함량이 다른 경향을 나타내었다. Zn 다음의 중금속함량은 Cu, Pb, Cd의 순으로 그 농도를 나타내었다.

• The Korean Journal of Malacology
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• v.7 no.1
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• pp.58-65
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• 1991

A study on the distribution and community structure of the benthic molluscan shells of the southern coastral area in Cheju Island was carried out from August 1990 to July 1991. The benthic molluscan shells collected and identified from 8 stations were composed of 3 classes, 7 orders, 22 families and 59 species. The number of appearance species from station 1 to station 8 were 22, 35, 32, 26, 28, 24, 32 and 31 species respectively. the first dominant species of the upper intertidal zone of the 8 stations were Nodilittorina exigua, those of the middle zones were Monodonta neritoides from st.1 to St.5, but the second dominant species were not uniftom at ach station.

• The Korean Journal of Malacology
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• v.4 no.1
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• pp.42-49
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• 1988

The chromosome of Cipangopaludina chinensis malleata Chunchon area in 1988 was analysed by using aceto-orcein squash techniques of spermatogonial tissues to obtain mitotic and meiotic chromosomes. The chromosome cycle did not differ, in general, from that found in other snails, C. chinensis malleata has 18 diploid chromosomes and they were identified and classified into 2 groups. The mitotic chromosome complement of this species consists of 2 pairs of metacentric and 7 pairs of submetacentric chromosomes, Spermatogonial metaphase chromosomes range in length from 4.10 ${\mu}{\textrm}{m}$ for the largest pair to 2.20 ${\mu}{\textrm}{m}$ for the smallest pair.

• The Korean Journal of Malacology
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• v.15 no.2
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• pp.127-131
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• 1999

Changes in Oxygen consumption and filtration rates were investigated to understand physiological rhythms for 24 hours of the Manila clam, Ruditapes philippinarum. physiological rhythms in the oxygen consumption and filtration rates at 15$^{\circ}C$ and 25$^{\circ}C$ were showed diurnal tidal rhythms, appearing two peaks for 24 hours: maximum at night-high tide and minimum at day-low tide. No rapid variations in oxygen consumption and filtration rates for 24 hours appeared at two different water temperatures.

• The Korean Journal of Malacology
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• v.15 no.2
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• pp.81-92
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• 1999

The histochemical, cytochemical, and immunocytochemical investigations were conducted to find out the cellulase activity in the accessory glands of the digestive system of the oriental land snail Nesiohelix samarangae under the LM, SEM, and TEM. The cellulase activity was shown in the epithelium of th digestive gland by labelling with the immunogold (protein-A gold) particles. The epithelial cells showing the cellulase activity were Type 1 and Type 3 cells out of five types of the epithelial cells of the digestive gland. None of epithelial cells of the mucus gland and the salivary gland and the salivary gland were not labeled with the immunogold particles.

• The Korean Journal of Malacology
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• v.15 no.1
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• pp.13-20
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• 1999

A horizontal starch gel electrophoresis for enzyme proteins extracted from three Korean species and one Chinese species of Semisulcospira was carried out in order to elucidate their genetic relationships. A total of 10 enzymes were employed in three different of buffer systems. Two loci from each enzyme of GAPDH, GOT, ICDH, IDH and PEP(VL); three loci from each of three enzymes, EST, PEP(LGG) and PGDH; and five loci from GPI were observed. Most of the loci in three pleurocerid species employed showed homozygous monomorphic banding patterns and some of them were specific as genetic markers between two different species. However, EST-2, PEP(LGG-3) and PGDH-1 loci in Korean S. libertina and PEP(LGG-3), PGM-1 and PGM-2 loci in Chinese S. libertina showed polymorphic banding patterns. Three Korean Semisulcospira species including S. libertina were more closely clustered in a dendrogram within the range of genetic identity values of 0.818-0.936, and these clusters were lineated with Chinese S. libertina at the value of 0.621.

• The Korean Journal of Malacology
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• v.24 no.2
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• pp.81-87
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• 2008

Distribution, population structure, and growth of the bivalve Protothaca euglypta were investigated for clams collected from the northwestern part of the East Sea of Russia. This species is distributed in further northern area than it was found earlier. In the southern area, this clam is found in the intertidal zone, up to 8 m in depth. It is one of the most numerous infaunal species of bivalves, and protected to wave action in the gravel-pebble and sand with rubble biotope. Population density of P. euglypta reaches 500 $spc./m^2$, and biomass 2 $kg/m^2$. Size and age composition of the local settlements and allometric growth of P. euglypta depend on a biotope. The growth rate of P. euglypta considerably reduces in case of the northern boundary area, whereas life span increases.