POLYZOA. 267 



Polypidom creeping, adherent and ramous; the cells 



in one or more series. ALECTO. 

 Family II. Polypidoms confervoid, jointed. CRISIAD.E. 

 Polype-cells uniserial. CRISIDIA. 

 Polype-cells biserial. CRISIA. 



** Polypidoms calcareous or membrane-calcareous, multi- 

 form, composed of oblong or oviform cells, whose 

 subterminal aperture is closed by a membranous fold 

 or operculum. CELLIPORINA. 



Family III. Polypidoms branched in a confervoid man- 

 ner; cells oblong; no ovarian capsules. EUCRA- 

 TIAD.E. 

 t The polypidom erect. 



Cells produced in a single linear series. EUCRATEA. 

 Cells geminate. GEMELLARIA. 

 tt The polypidoms creeping, adnate. 



Cells linked, anastomosing. HIPPOTHOA. 

 Cells scattered, erect. ANGUINARIA. 

 Family IV. Polypidoms massive or crustaceous, com- 

 posed of ovate cells in juxtaposition ; the aperture 

 often furnished with a globular capsule. CELLI- 

 PORID^E. 

 Polypidom lobed or ramous ; cells heaped. CELLIPORA. 



