118 
DESMEPOBID^. 
Dimensions. 
Height of zoarium 
Width of zoarium 
Diameter of stems 
Diameter of peristomal groups 
Diameter of apertures 
mm. mm. 
12 ... 7 
7 ... 7 
1 - 1-0 ... 1 
•7 ... -6--7 
.. probably -1 ... — 
Distkib. — Cenomanian — Unter Planer; Plauen, Sa.xony. 
Aff. — T his species differs emphatically from I), semicylindrica by its thicker 
branches and the less regular distribution of the groups of apertures. Instead 
of the apertures occurring in small groups, arranged in two lines, one along 
each side of the stem, they are irregularly scattered and may arise from the 
front of the stems. 
One specimen included by von Reuss (viz. op. cit. pi. xxx. figs. So, b) is 
probably a Homceosolen, and may be a branch of the same species as the 
“ Truncatula aculeata,'’' figured on the same plate (fig. 4) ; but this cannot 
be decided without knowledge of the obverse surface of the stem in question. 
SEMICYTIS, d’Orbigny, 1854. 
[Bry. Cret. p. 1048.] 
Synonyms. 
Osculipora, pars^ d’Orbigny, 18o0. 
Desmeopora^ pars, Bucaille, 1890; Ulrich, 1900. 
Diagnosis. 
Desmeporidae with a zoarium fixed by a broad base, supporting 
a narrow vertical peduncle, which may branch above into 
a tuft. 
The branches may divide dichotomously and may be pinnate. 
Each branch consists of a round axis, which gives off above 
a series of pinnules or tufts. These pinnules or tufts may 
arise independently from the axis or from a ridge running 
along the obverse surface of the stem. 
Type Species. 
(d’Orbigny), 1850. Senonian: France; Fecamp, 
Seine-Inf erieure. 
Affinities. 
D’Orbigny included four species in this genus. His first species 
and the most suitable type, S. rugosa, has the branches divided 
into a cancellate axis on the reverse side, with a ridge bearing the 
zooecial apertures on the obverse. D’Orbigny’ s Semicytis fene strata 
and disparilis, on the other hand, according to the definitions 
