Observations on the ligament of Mytilus edulis.

نویسنده

  • E R TRUEMAN
چکیده

1. The ligament of Mytilus edulis is situated between the valves of the shell imme diately below the dorsal margin and may be divided into two main layers, the inner and the outer, the principal features of which appear to correspond with those of other bivalves. 2. The outer layer is subjected to a tensile strain transverse to the longitudinal plane of the shell, which is imposed by the addition of the inner layer. This strain is increased when the valves are closed. At the same time the inner layer is compressed. It is significant, however, that the birefringence of the main outer layer is much smaller than in Tellina. 3. The prodissoconch has a small internal ligament which is replaced by the normal adult structure as the posterior dorsal margin of the young mussel is extended. 4. The axis about which the valves open is situated along a line drawn between the two main layers. Anteriorly the adult ligament becomes split and ceases to function. Possible explanations are suggested.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Genetic, Ecological and Morphological Distinctness of the Blue Mussels Mytilus trossulus Gould and M. edulis L. in the White Sea

Two blue mussel lineages of Pliocene origin, Mytilus edulis (ME) and M. trossulus (MT), co-occur and hybridize in several regions on the shores of the North Atlantic. The two species were distinguished from each other by molecular methods in the 1980s, and a large amount of comparative data on them has been accumulated since that time. However, while ME and MT are now routinely distinguished by...

متن کامل

Local adaptation and species segregation in two mussel (Mytilus edulis x Mytilus trossulus) hybrid zones.

Few marine hybrid zones have been studied extensively, the major exception being the hybrid zone between the mussels Mytilus edulis and Mytilus galloprovincialis in southwestern Europe. Here, we focus on two less studied hybrid zones that also involve Mytilus spp.; Mytilus edulis and Mytilus trossulus are sympatric and hybridize on both western and eastern coasts of the Atlantic Ocean. We revie...

متن کامل

Endocrine Disruption, Reproductive Cycle and Pollutants in Blue Mussel Mytilus edulis

Adult Mytilus edulis were exposed to environmentally relevant concentrations of 17β-estradiol in seawater for 10 days. Exposure was performed to assess effects on vitellogenin mRNA expression during early gametogenesis stages. The results show an increase in VTG expression, in contrast with previous experiments where no statistically significant change in the expression of VTG in ripe mussels w...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:
  • The Quarterly journal of microscopical science

دوره 91 3  شماره 

صفحات  -

تاریخ انتشار 1950