hydranth


Also found in: Dictionary, Encyclopedia, Wikipedia.

hydranth

the normal COELENTERATE polyp, having a mouth surrounded by tentacles, found in most colonial forms.
Mentioned in ?
References in periodicals archive ?
In addition two frustules were seen "in vivo" budding off from a hydranth. After these findings, careful inspection of the plants (Egeria sp.) and bivalves (Diplon sp.) remaining in the aquaria failed to reveal additional C.
Nematocysts also scattered along all the hydranth's surface.
The small hydranth is seldom found in nature and is known mostly from aquarium studies.
Hydranth with sub-spherical hypostome and 18-20 sort tentacles, about 2.6 mm long.
Hydranth more or less ellipsoid, with 10-16 long tentacles, about 465 mm long.
The number of tentacles in the 13 hydranths examined in this study ranged from 7 to 23.
To accurately determine the number and size range of nematocysts per hydranth, 50-75 nematocysts of each type were measured from three hydranths from the Woods Hole population; this population was chosen because it was the largest colony of our study populations.
Population P Mean Standard Mean Difference value ([mu]m) deviation hydranth SD of hydranth ([mu]m) ([mu]m) SD ([mu]m) CL 0.007 8.44 0.35 0.55 0.17 DP <.001 7.88 0.19 0.40 0.12 E 0.003 8.07 0.22 0.60 0.36 FN <.001 7.94 0.26 0.43 0.32 H <.001 7,96 0.19 0.41 0.14 J < .001 8.15 0.21 0.46 0.26 LE < .001 7.62 0.35 0.74 0.44 LO <.001 7.56 0.27 0.44 0.27 LS <.001 7.69 0.17 0.43 0.18 NR <.001 8.35 0.41 0.74 0.43 SL <.001 7.83 0.18 0.44 0.25 SO <.001 8.04 0.25 0.54 0.25 V <.001 8.07 0.43 0.52 0.24 WH2 0.001 7.73 0.29 0.62 0.16 P values are from a one-way ANOVA between averages of individual hydranth measurements for each population.
A number of experiments have been made that seem to indicate that the temporary inhibition of the development of the basal hydranth in Tubularia is not the result either of the using up of materials by the oral hydranth, or of the setting free of inhibitory stuff.
It was found that the basal ends of the (A) pieces did not develop faster than those of the (B) pieces, showing that the changes at the basal end of (A) are not progressing, but are held in check by the developing oral hydranth.
(Pyefinch and Downing, 1949; Berrill, 1952; Hawes, 1958; Lemire and Bourget, 1996), concluding that, because of their direct development, these larvae should be considered merely hydranths with rudimentary stalks, or only juvenile polyps.
Zooanthellate digestive cells of Myrionema ambionense have two general shapes: columnar from the hypostome (= cup) region of the hydranth (also called digestive cells here, Fig.