360 
CAXCELLATA. 
into jointed segments. There are neither nicsopores nor 
avicularia. 
Affinities. 
This gi’oiip of Bryozoa may he described as Cyclostomata 
Tuhulata with cancellate walls. This foim of skeleton \\ as 
apparently developed in the early paid of the Cretaceous peiiod, 
fi’om the most specialized of the Idmonids. "\Miether the group 
is monophyletic is doubtful ; but it is a convenient suborder, 
analogous to the group of Perforata among Madi’eporarian corals. 
It is adoj)ted for descriptive pui’poses. 
The group is considered before its proper position, as it sliould 
follow the Pasciculate section of Cyclostomata Tuhulata. The 
cancellous character of the walls is due to the presence in them 
of a series of maculae. This teim was suggested in 1893 for tlie 
cavities in the walls of zooecia (Gregory, “British Palaeogene 
Biyozoa”: Trans. Zool. 8oc. vol. xiii. pt. 6, 1893, p. 221). They 
correspond in part with the ‘ pores d’origelles ’ of Jullien, the 
‘pores intermediaires’ of d’Orhigny, the ‘ cavites intersqueletticiues ’ 
of Pergens, and in part to the ‘ dutinky kosterne ’ and ‘ pridavne 
hunky’ of Pocta, and the ‘ mikroskopischen Porencaniile ’ of Marsson. 
The maculae differ from mesopores, which are rudimentary zooecia ; 
and from interzooecial spaces. 
Pamily HOEXEKID^E. 
Synonyms. 
Sorneridce, Hincks, 1879. 
Idmoniidce, pars, Busk, 1875. 
Crisinidce, pars, d Orbigny, 1853. 
Caveidce, pars, d’Orbigny, 1853. 
Diagnosis. 
Cyclostomata Cancellata in which the zoarium is erect and 
branched. The apertures occur only on the obverse side ; 
they are arranged in simple lines or are quite irregular. ' The 
reverse face may he marked by interzooecial depressions, or 
may he covered by a laminated e]Ditheca traversed by tuhuli. 
Maculae regular or irreanlar. 
