238 MARINE BIOLOGY OF THE SUDANESE RED SHA. 
zocecia. There is no gizzard, there are a considerable number of tentacles ; 
some are oviparous and produce Cyphonautes. 
The genera included are Aleyonidiwn, Flustrella, Pherusa, Clavopora, 
and Lobiancopora. This group has been recognised as Alcyonellea, but has 
also received other names. The remainder have been grouped together as 
Stolonifera, Ehlers, but it seems to me that two quite distinct things have 
been called stolons. The genus Hypophorella of Ehlers, which is really 
the type of the Stolonifera, has a creeping or erect tubular filamentous 
stolon or rhizome—that is, a very slender and delicate tube expanding at 
intervals for the production of zocecia, as in Hypophorella, Farella, Triticella, 
Valkeria, Mimosella ; so that the term rhizome used by Foettinger and Potts 
in describing Pedicellina seems very appropriate, as the growth is usually 
similar to the rhizome of plants. 
(2) Next we have a group with a free thick stem from which the zocecia 
grow direct from various parts, as in Zoobotryon, Amathia, &c., and. none: 
seem to grow from a thin segmented creeping filament, though in Amathia * 
the stem at first spreads out on the supporting surface ; and then in places — 
on the stem a watch-glass holiow is formed from which the sudcolonies arise. 
In all the genera with these uniform thick free stems there is a gizzard, and 
the number of tentacles is usually small (8-10). The genera included are 
Zoobotryon, with its synonym or ally Bowerbankia ; Amathia; Vesicularia ; 
and Buskia socialist, Hincks ; Avenella (?), Dalzell ; Cryptopolyzoon, Dendy. 
It will be best to restrict the name Vesicularina to this group, although both 
Ehlers and Hincks put the various species under the Stolonifera. 
(3) Lastly, the Stolonifera as now limited have, as a rule, no gizzard, but 
Joyeux-Laffuie mentions one as a generic character in // ypophorella, though 
without further particulars ; however, as nothing of the kind is mentioned or 
figured by Ehlers, I take it that there is no gizzard in Hypophorella, though 
until sections have been made there will be some uncertainty. Some text-. 
books have, however, incorrectly given the gizzard as a character of the 
whole Ctenostomata. Hincks mentions a gizzard in Avenella, in which the 
number of tentacles is given as 20-24. It is clear that search should always 
be made for the gizzard, although we do not at present know what the 
classificatory value may be. 
As stated, in Hypophorella, Furella, Valkeria, Triticella, there is a delicate 
rhizome which expands at intervals, and from this expansion one or a pair of 
zooecia grow, and also one or two fresh creeping filaments or radicles at right 
angles to the parent tube ; or from the expansion a nodular attached growth 
may take place on each side, and from each nodule a fresh pair may grow 
forming groups of zocecia as in Valkeria. Throughout the group there is a 
* A short radicle attachment is thrown out here and there for attachment. 
+ See p. 241. 
