very thick with two long opposite tentacles starting near to the top of the umbrella, ending far from the bell, without secondary tentacles.
Multiple attempts to record from the exumbrella
of three different animals, with either electrical or mechanical stimulation of the exumbrella
, tentacles, subumbrella, or rhopalia failed to demonstrate an exumbrellar conducting system.
All discoids are bed-parallel; none exhibit evidence for folding, tearing, twisting, agglomeration in ripple troughs, or preservation indicative of a convex body (e.g., an exumbrella
) that has been preserved upside-down.
Tissue pieces were dissected from small and large adult Aurelia, including pieces from the margin (including tentacles), from the more peripheral subumbrella and more central subumbrella, the exumbrella
, and the manubrium.
Other parts of scyphomedusae, including tentacles, manubrium, and exumbrella
, show similar double staining, with the FMRFamide-immunoreactive networks including putative sensory cells.
When making contact with a jellyfish, phyilosomas first cling onto its exumbrella
, feed on its tentacles or oral arms, and then consume the exumbrella
Nemopilema, as well as Aurelia aurita, has eight rhopalia at the margin of the exumbrella
4), [d.sub.stopping] was determined from the distance between the inner surface of the exumbrella
and the manubrium.
Bell diameter, the distance (cm) between distal ends of rhopalia on a chord bisecting a medusa lying exumbrella
surface down on the measuring table, was our Standard measurement of medusa size (Dawson 2003, 2005b, c).
A frenulum interrupts the ring of tissue of the velarium, but this interruption does not extend through to the exumbrella
. The frenulum represents an inward and upward fold of subumbrellar tissue that forms a double muscle layer separated by a narrow wedge of mesoglea (Fig.
smooth, without ridges or visible clusters of nematocysts.
Marginal sense organs: 8; each with two rhopaliar cones, one from exumbrella
and extending inward, one between and formed by junction of adjacent lappet borders and directed upward.