Hydroid: stolonal, hydranth 1-6 mm high, with very short pedicel, perisarc smooth.
The small hydranth is seldom found in nature and is known mostly from aquarium studies.
Hydranth ovoid, with 20 to 32 thin tentacles, about 1.
Hydranth with sub-spherical hypostome and 18-20 sort tentacles, about 2.
1978) reported that only one gonophore was usually present below a single hydranth, but occasionally two gonophores were present.
1978) proposed that increased chloride concentrations tend to produce larger colonies with more tentacles per hydranth in habitats in Texas.
Freshwater colonies were shortest in height, had the least branching, had slowest growth, and had short, thick hydranths
: marine (30[per thousand]) colonies were intermediate in size and had intermediate branching, growth rate, and hydranth
Since every part of the stem of Tubularia is capable of producing a hydranth
the inhibition of basal development is obviously due to the presence of a hydranth
or of a developing hydranth
at the oral end.
In these juvenile polyps, the cushion-like tissue disappeared into the endoderm of the aboral half, and many digestive gland cells developed in the endoderm of the oral half of the hydranth
Surface areas were determined from length and width (average of widths at top and bottom of cell), measured for rectangular hydranth
cells, and diameter for circular tentacle cells.
infrastructure and cytochem-istry of glycogen-containing vacuoles in gastrodermal cells in developing hydranths
of a hydromedusan coelenterate.
The regression-replacement cycle of hydranths
of Obelia and Campanularia.