@article{oai:ir.kagoshima-u.ac.jp:00012790,
 author = {WADA, Seiji},
 issue = {2},
 journal = {鹿児島大学水産学部紀要=Memoirs of Faculty of Fisheries Kagoshima University},
 month = {2016-10-31},
 note = {The Japanese rock oyster, Crassostrea echinata, was mainly used as materials. From the morphology of the attached and the once-attached and later expelled spermatozoa, it is inferred that, on attachment, every spermatozoon will effect stimulation to the egg through the acrosome filament. The rate of fertilization was studied with varying sperm concentrations or at different intervals after insemination. It was found that some of the eggs remained unfertilized under circumstances which satisfied attachment of at least a single, probably several, spermatozoa to every one of the eggs. Fertilization in these unfertilized eggs was accomplished on subsequent sperm attachment. This problem was further approached in this paper. Since an unfertilized egg is a kind of irritable systems which is highly sensitive to sperm stimulation, some excitation should be evoked in it with stimulation from any functional spermatozoon. If the stimulation be subliminal, the excited state will facilitate the initiation of fertilization impulse by an immediately following attachment of another spermatozoon. The writer believes this is the most plausible explanation for the fact in question. Some pieces of supporting evidence have been presented. It is likely the number of spermatozoa which is needed to achieve fertilization correlates to the grade of maturity of the egg and to the strength of stimulus from spermatozoa, both of which will vary individually.},
 pages = {109--126},
 title = {Studies on the Fertilization of Pelecypod Gametes II : Facilitation of Fertilization by Attachment to An Egg of Plural Spermatozoa},
 volume = {12},
 year = {}
}