297 
drotheca. It is ' however completely closed outwardly. Also in 
A. coei (PI. I\, fig‘» 23) a number of the corresponding projections 
contain a distinet innoi cavity, but in most of tbem it seems to 
be completely filled by a chitinous secretion. 
According to the investigations contained in this 
paper I must maintain that th Q Carnpanulinidae have devel- 
oped from the Lafoeidae or partly from the Campanulariidae. 
and that the Sertulariidac must be de rived from that 
gro up of the Campanulinidae in which the whole roof 
of the hydi otheca has b een trau sform ed into an oper- 
culum. 
Thujaria (Fleming) Lev. 
llie apeitme is veitical or obliquely ascending' and provided 
with an abeauline sinus, in which is fixed an opercular membrane, 
the distal part of which is a free valve. 
The gonothecae of the species hitherto examined are smooth 
without transverse rings and without spines. 
In most biseiial species the hydrothecae are almost symmet¬ 
ri 0 ^ being only in a very slight degree turned towards the frontal 
face 1 ) of the colony. 
Of this genus I have examined the folio wing species: Th. 
thuja (L.) Th. lonchitis (Ellis & Sol.), Th. articulata (Pall.), Th. 
lichenastrum (Pall.), Th. annulata Krp., Th. carica Lev., Th. 
polycarpa Popp., Th. variabilis Markt., Th. cedrina (L.), Th. 
cupressoides (Lepech.), Th. sinuosa Bale, Th. tuba (Bale), Th. 
desmoides (Torr.), Th. hexodon (Bale), Th. juncea (Vanh.), Th. 
Hartlaubi (Nutt.), Th. Hincksi (Mer.), Th. pinnata (Mer.), Th. 
cylindrica (Clark.). 
> 
r Sertularia (L.) Lev. 
Dynamena (Lamour.) 
The aperture is oblique and provided with two lateral teeth, 
between which there are found a deeper abeauline and a lower 
-—— __ _» 
) »Irontal« we call that face of the colony on which the gonothecae 
are placed. 
