The secretion forms a basal plate and radiating partitions between the mesenteriesin the cavity of the animal, and also surrounds the polyp like a cup.
The larger chamber next becomes divided by two fresh mesenteries into three, and a similar division then takes place in the smaller chamber.
The mesenteries consist of a fold of hypoblast with a prolongation of the epiblast between the two limbs of the fold.
The stage with six chambers is almost immediately succeeded by one with eight, owing to the appearance of two fresh mesenteries in the second-formed set of chambers.
A layer of circular muscles is formed at a late period from the epiblast, but the longitudinal muscles of the mesenterieson the inner side of the homogeneous membrane are regarded by Kowalevsky as hypoblastic.
In each of these rings is a dilation of the stomach, and a section of each of the four rudimentary mesenteries described in connection with the development of the Scyphistoma.
Two mesenteries now make their appearance transversely to the long axis of the mouth, which divide the enteric cavity into two unequal chambers.
They imperfectly divide the stomach into four chambers, to each of which one of the primary tentacles corresponds; they may be regarded as homologous with the mesenteries of the Actinozoa.
Defn: Having the parts in eights; as, an octamerous flower; octamerous mesenteries in polyps.
The mesentery proper is connected with the jejunum and ilium, the other mesenteriesbeing called mesoc, mesocolon, mesorectum, etc.
The mesentery proper is connected with the jejunum and ilium, the other mesenteries being called mesoc
Schematic profile view of primitive mesenteries with formation of omental bursa and developing spleen and pancreas.
Again the mesenteriesare treated here as if they formed definite and well-defined membranes from the beginning--without reference to the abdominal organs with which they are associated.
The sexual cells are borne on the mesenteriesin positions irrespective of obvious developmental radii.
The first twelve mesenteries are disposed in couples, and do not differ from those of Actinia except in size.
The sulcar and sulcular pairs ofmesenteries are short, the sulco-lateral and sulculo-lateral pairs are a little longer, but the two transverse are very large and are the only mesenteries which bear gonads.
Externally they resemble ordinary sea-anemones, but there is only one ciliated groove, the sulcus, in the stomodaeum, and the mesenteriesare arranged on a peculiar pattern.
Moreover, there are some modern corals in which the secondary cycle of mesenteriesdeparts from the Actinian plan.
The mesenteries of the first cycle are complete (i.
The mesenteries are provided with well-developed longitudinal retractor muscles, supported on longitudinal folds or plaits of the mesogloea, so that in cross-section they have a branched appearance.
Hence in corals in which there is only a single cycle of mesenteries the septa are correspondingly few in number; where several cycles of mesenteries are present the septa are correspondingly numerous.
In the Cerianthidea, as in the Zoanthidea, much as the adult arrangement of mesenteries differs from that of Actinia, the derivation from an Edwardsia stock is obvious.
These muscle-banners, as they are called, have a highly characteristic arrangement; they are all situated on those faces of the mesenterieswhich look towards the sulcus.
In the common sea-anemone, Actinia equina (which has already been quoted as a type of Anthozoan structure), the mesenteries are numerous and are arranged in cycles.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "mesenteries" in a variety of sentences. We hope that you will now be able to make sentences using this word.
