23 
place. In dried colonies of Catenaria parasitica I have sometimes 
found the zooecial rows ending in sirailar cyliudrical internodes, 
but in this species I have not yet been able to find traces of a 
similar raetamorphose. The distal wall of Chlidonia is provided 
with one single-pored rosette-plate, while in Cat. parasitica there 
is a transverse row of similar rosette-plates. A simple operculum. 
Diazeuxidae Jullien. To this family, at present only con- 
taiuing the genus Diazeuxia, I must further refer Chorizopora 
Brognarti, Microporella impressa {Haplopoma n. g.), Schizoporella 
venusta {Trypostega n. g.) and the species of the genus Hippothoa 
which I think must be merged in Diazeuxia. While in all other 
families of Camarostega the zooecia in the growing edge of the 
colony are only calcified in their posterior part, in this family the 
calcification always keeps pace with the growth. The thin-walled, 
finely striated zooecia are provided with pore-chambers, and the ooe- 
cia which possess an atrium, and are connected with a rudimen- 
tary distal wall are covered either by kenozooecia {Diazeuxia, Hip¬ 
pothoa, Haploporna) or by rudimentary zooecia {Trypostega) or hy 
avicularia {Chorizopora). 
Reteporidae. This very natural family not only contains spe¬ 
cies growing in frce ramose colonies, with or without reticulation, 
but also a iiumber of incrusting species (f. i. Schizotheca fissa, Rhyn- 
chopora hispinosa, Schizoporella scintillans). The zooecia, whose 
walls are very compact and strongly calcified, are provided with a 
distal how, generally headed, and with very few single-pored ro¬ 
sette-plates. Generally the distal wall has only a single, and each 
lateral wall two rosette-plates. The ooecia are hypostegial and 
originally free ^). In all the species growing in free colonies the 
hack-side of the colony is invested with a layer of kenozooecia, very 
seldom possessing a distinet cavity (f. i. in R. tesselata, R. lata, 
R. Wallichiana) and immediately continued in the layer of keno- 
G. M. K. Leviusen, Mosdyr, Tab. VI, Fig. 27. 
