80 VINE : BRITISH PALEOZOIC CTENOSTOMATOUS POLYZOA. 
base, deciduous, destitute of a membranous area. Zoarium, repent, 
or erect.* Hincks, p. 512. 
In the Genus Vesicularia, the type of which is V. spinosa, 
Linn. (p. 533), the Zoarium is phytoid and rooted by a fibrous base. 
The endosarc of this species consists of a slender thread, running 
through the tubular stem from cell to cell, and communicating with 
each other through an orifice at the base. (See Hincks, p. 514, pi. 73). 
In the Genus Bowerbankia, Farre (p. 518), the Zooecia are ovate, 
disjunct, clustered, and the Zoaria are either repent or erect. In one 
species B. caudata Hincks the stem is creeping, the Zooecia are 
elongate and sub-cylindrical. Five species of Bowerbankia are 
described and illustrated by Hincks, but four of these are of no im- 
portance for the elucidation of my present labours, but the student 
should refer to the description of them nevertheless for special 
information (pi. 73-75 and 76). 
Family V. BusKiiDiE, Brit. Mar. Polyzoa, p. 531. 
In this family the Zooecia are contracted below, not continuous 
with the creeping stolon, with no aperture on the ventral surface. It 
may be well, however, to refer the student to the illustrations which 
show the peculiar stolon of B. nitens (p. 532), and also of the 
arrangement of the whole on the erect stem of Hippuraria Egertoni, 
(pi. 78, fig. 1), but beyond the mere similarity no real identity could 
be established between the fossil and recent species. 
Family VI. Cylindraciida, p. 534. 
In this family the Zooecia are not contracted at the base, but 
they are closely united to the stem at the base, and they are not 
deciduous. 
Family Valkeriid^:, p. 551. 
The Zooecia of the species of this family are contracted below, 
and they are also deciduous. In the genus Valkeria the Zoarium is 
both erect and repent, and the ovate Zooecia are clustered together. 
* The italicised parts of sentences is for the purpose of drawing attention 
to special features. 
