Resting buds. The resting buds are spindle-shaped.
Kraepelin recognized two species in the genus mainly by their method of growth and the number of tentacles. In his P. mülleri the zoarium is always recumbent and the polypide has 8 tentacles, whereas in P. articulata or ehrenbergi the tentacles number 16 and upright branches are usually developed. It is probable, however, that the former species should be assigned to Victorella, for it is often difficult to distinguish Paludicella from young specimens of Victorella unless the latter bear adventitious terminal buds. The gizzard of Victorella can be detected in well-preserved material even under a fairly low power of the microscope, and I have examined specimens of what I believe to be the adult of mülleri which certainly belong to that genus.
It is always difficult to see the collar of Paludicella, because of its transparency and because of the fact that its pleats are apparently not strengthened by chitinous rods as is usually the case. Allman neither mentions it in his description of the genus nor shows it in his figures, and Loppens denies its existence, but it is figured by Kraepelin and can always be detected in well-preserved specimens, if they are examined carefully. If the collar were actually absent, its absence would separate Paludicella not only from Victorella and Pottsiella, but also from all other ctenostomes. In any case, Victorella is distinguished from Paludicella and Pottsiella by anatomical peculiarities (e. g., the possession of a gizzard and the absence of a second funiculus) that may ultimately be considered sufficiently great to justify its recognition as the type and only genus of a separate family or subfamily.
The description of Paludicella is included here on account of Carter's identification of the specimens he found at Bombay; but its occurrence in India is very doubtful.
Genus 2. VICTORELLA, Kent.
Victorella, Kent, Q. J. Micr. Sci. x, p. 34 (1870). Victorella, Hincks, Brit. Marine Polyzoa, p. 559 (1880). Victorella, Kraepelin, Deutsch. Süsswasserbryozoen, i, p. 93 (1887).
Type, Victorella pavida, Kent.
Zoarium. The zoarium consists primarily of a number of erect or semi-erect tubular zoœcia joined together at the base in a cruciform manner by slender tubules, but complications are introduced by the fact that adventitious buds and tubules are produced, often in large numbers, round the terminal region of the zoœcia, and that these buds are often separated from their parent zoœcium by a tubule of considerable length, and take root among other zoœcia at a distance from their point of origin. A tangled mass may thus be formed in which it is difficult to recognize the regular arrangement of the zoœcia that can be readily detached at the growing points of the zoarium.
Zoœcia. The zoœcia when young closely resemble those of Paludicella, but as they grow the terminal upturned part increases rapidly, while the horizontal basal part remains almost stationary and finally appears as a mere swelling at the base of an almost vertical tube, in which by far the greater part, if not the whole, of the polypide is contained. Round the terminal part of this tube adventitious buds and tubules are arranged more or less regularly. There are no parietal muscles.
Polypide. The polypide has 8 slender tentacles, which are thickly covered with short hairs. The basal part of the œsophagus forms a thin-walled sac (the "gizzard") constricted off from the upper portion and bearing internally a thin structureless membrane. Circular muscles exist in its wall but are not strongly developed on its upper part. There is a single funiculus, which connects the posterior end of the stomach with the base of the zoœcium. The ovaries and testes are borne on the endocyst, not in connection with the funiculus.