Mesoblast sentence example
- In origin the vascular system is due to a fusion of spaces which arise in the mesoblast of the larva.
- Bergh (for Lumbricus and Criodrilus), whose figures show a derivation of the entire nephridium from mesoblast, and an absence of any connexion between successive nephridia by any continuous band, epiblastic or mesoblastic. A midway position is taken up by Wilson, who asserts the mesoblastic formation of the funnel, but also asserts the presence of a continuous band of epiblast from which certainly the terminal vesicle of the nephridium, and doubtfully the glandular part of the tube is derived.
- The segmentation is of the mesoblast to begin with, and appears later behind the mouth, the part anterior to this becoming the prostomium of the adult.
- The rhynchocoel is formed by a split which appears in the mesoblast surrounding the epiblastic pit which is the forerunner of the proboscis.
- The proboscis is an invagination from the epiblast; the proboscidian sheath appears in the mesoblast, but is perhaps originally derived from the hypoblast.Advertisement
- The mesoblast multiplies its cells, which become partly muscular and partly skeleto-trophic. Centro-dorsally now appears the embyronic shell-gland.
- The mesoblast of the cephalic (naupliar) region probably arises in connexion with the lips of the blastopore and consists of loosely-connected cells or mesenchyme.