CEEIOPOHA. 
157 
De Blainville did not definitely state that the zooecia were of 
uniform size in Ceriopora, but this fact follows from his diagnosis 
of Heteropora, wherein he includes ^ those species of Ceriopora 
which have the “ Cellules rondes, poriformes, completement 
immergees, de deux sortes, les unes hien plus grandes que les 
autres.” 
The course adopted by de Blainville was essentially that 
followed by d’Orbigny in 1854, as he placed Ceriopora in his 
family the Cavidae, a family which is “ sans pores speciaux, ni 
pores intermediaires. Les cellules egales . . The essential 
difference between Ceriopora and Seteropora is that Ceriopora is 
monomorphic and Heteropora dimorphic. 
The genus Ceriopora^ as defined by d’Orhigny in 1854, was 
limited to five species, of which two, tuhiporacea and milleporacea^ 
have been assigned (Vol. I. pp. 350-1) to Inversaria\ the three 
remaining species are C. iruncata (Mich.), C. digitalis (d’Orb.), and 
C. micropora, Goldf. As the last of these was the only one also 
placed by Goldf uss in the genus, it is the proper type species. 
The structure of Ceriopora was represented by de Blainville 
in 1830 and by d’Orhigny in 1854 as multilamellar ; to quote 
d’Orbigny’s own terms (Bry. Cret. p. 1029) each branch “ est 
pourvue de plusieurs couches superposees et s’enveloppant les unes 
les autres.” But in 1850 d’Orbigny had founded the genus 
Reptomulticava for the multilamellar species and retained Ceriopora 
for the massive, non-lamellar species. D’Orbigny, however, 
abandoned this arrangement in 1854, and then used Reptomulticava 
for the nodular and Ceriopora for the branched species. 
His original view of 1850 seems, however, to he better than 
the amendment, and I prefer to follow the first definition, for 
the lamellar structure seems more important than the difference 
between nodular or branched zoaria. A certain amount of marginal 
lamellation must be expected in massive Bryozoa, for they increase 
in breadth by the overlap of the upper growing edge. The 
marginal or basal lamellation thus caused can be seen in d’Orhigny’s 
figure of C. digitalis (Bry. Cret. pi. 791, fig. 9), and is suggested 
in von Hagenow’s figure of the broken base of C. micropora (Bry* 
maastr. Kr. pi. v. fig. 45), where the central area consists of 
vertical zooecia seen in transverse section, while the outer horizontal 
1 Ibid. p. 381. 
