The family Paludicellidæ consists of three genera which may be distinguished as follows:--
I. Orifice terminal; main axis of the zooecium vertical; zooecia separated from one another by tubules. [A. Base of the zooecia not swollen; no adventitious buds POTTSIELLA.] B. Base of the zooecium swollen; adventitious buds produced near the tip VICTORELLA, p. 194. II. Orifice subterminal, distinctly on the dorsal surface; main axis of the zooecium horizontal (the zoarium being viewed from the dorsal surface); buds not produced at the tip of the zooecia PALUDICELLA, p. 192.
Of these three genera, _Pottsiella_ has not yet been found in India and is only known to occur in N. America. It consists of one species, _P. erecta_ (Potts) from the neighbourhood of Philadelphia in the United States.
_Victorella_ includes four species, _V. pavida_ known from England and Germany and said to occur in Australia, _V. mülleri_ from Germany (distinguished by possessing parietal muscles at the tip of the zooecia), _V. symbiotica_ from African lakes and _V. bengalensis_ from India. These species are closely related.
_Paludicella_ is stated by Carter to have been found in Bombay, but probably what he really found was the young stage of _V. bengalensis_. A single species is known in Europe and N. America, namely _P. ehrenbergi_, van Beneden (=_Alcyonella articulata_, Ehrenberg).
I have examined specimens of all the species of this family as yet known.
_Paludicella_, Gervais, Compt. Rend. iii, p. 797 (1836).
_Paludicella_, Allman, Mon. Fresh-Water Polyzoa, p. 113 (1857).
? _Paludicella_, Carter, Ann. Nat. Hist. (3) iii, p. 333 (1859).
_Paludicella_, Jullien, Bull. Soc. zool. France, x, p. 174 (1885).
_Paludicella_, Kraepelin, Deutsch. Süsswasserbryozoen, i, p. 96 (1887).
_Paludicella_, Loppens, Ann. Biol. lacustre, iv, p. 14 (1910).
_Zoarium._ The nature of the zoarium in this genus is well expressed by Ehrenberg's specific name "_articulata_," although the name was given under a false impression. The zooecia arise directly from one another in linear series with occasional side-branches. The side-branches are, however, often suppressed. The zoarium as a whole is either recumbent and adherent or at least partly vertical.