mesoglea

The presence of a definitive muscle cell layer within the mesoglea suggests that C.

Cannonball jellyfish (Stomoloplus meleagris) in the Gulf of Mexico are commonly infected with parasitic worms up to 4 mm in length that slowly crawl through the mesoglea. The worms lack all traces of internal organs but contain oval bodies resembling the calcium corpuscles found in cestodes.

These analyzed specimens of Gonionemus have: around a 10 mm width, four radial channels, a manubrium shorter than the umbrella cavity, a mouth with four lips slightly crenulated, four folded gonads along radial channels leaving the distal part free, between 40 and 44 hollow tentacles, each tentacle has ring-like nematocyst clusters and adhesive pads near the distal end, and one or two statocysts between successive tentacles enclosed in mesoglea near ring canal with a single endodermal club.

outer cell layer, an inner cell layer, and in between a thick gel called mesoglea. This gooey stuff contains muscle fibers that produce swimming pulsations.

At [T.sub.6], several changes were observed in the distal end of the rhopalium, where the crystal was enclosed by a new layer of mesoglea separating it from both the epidermis and the gastrodermis (Fig.

In all of these cases, descriptions depend on tested protocols in this group of organisms that can acquire a clear differentiation between the mesoglea and epithelial and muscle areas.

In my experience, the ability to visualize the bristles in living animals depends on attentive observation of either larvae immobilized under a coverslip or carefully oriented dissections of tissue slices of adult apical organs that allow views unobstructed by surrounding tissue and mesoglea. DIC microscopy is preferable to phase-contrast or bright-field optics for this purpose.

The study of the nematocysts of this species, as well as for many other cubozoans, is also made more difficult by the thick mesoglea, which gets hardened after fixation.

Between these two layers is the mesohyl, also known as the mesoglea, which forms the bulk of the sponge body.

Members of the phylum Cnidaria possess fibrillar and non-fibrillar collagenous proteins in their mesoglea. Their collagen is considered acellular, and is situated between the epidermal and gastrodermal cell layers (Tillet-Barret el al., 1992).