134 



Synopsis of the genera. 



1) On the basal surface a larger or smaller number of zooecia with 

 a vibraculum connected with a chamber, fi-om which a radical fibre 

 may issue (avicularia always present): 



2) The true vibraculum (the chamber for the radical fibres not in- 

 cluded) divided by a septum into a distal and a proximal space, the 

 former containing the muscles: 



3) The very large, claw-shaped vibracula, present on all zooecia, 

 ai'e directed obliquely inwards and basally, and meet from both sides 

 at acute angles in the middle of the basal side of the colony, which 

 they almost cover; the flagellum on one margin generally with pointed 

 teeth; the radical fibres, which spring only from the chamber con- 

 nected with the vibraculum, run down along the middle of the basal 

 side of the colony as a continuous, raised bundle; (the colony not 

 jointed) Caberea Lamouroux. 



3) The small, curved or angularly bent vibracula, not present on 

 all zooecia, are far from reaching the centre of the colony; the flagel- 

 lum without teeth; the radical fibres, of which some spring from the 

 chamber connected with the vibraculum, others from a rosette-plate 

 on the marginal zooecia, form a bundle along each lateral margin of 



the colony Caberiella n. g. 



2) The true vibraculum not divided into two spaces (the flagellum 

 without teeth; the colony generally jointed; the vibracula covering 

 only a smaller part of the basal surface o£ the colony): 



4) The ooecium enclosed in the widened proximal half of a large 

 avicularium, the distal, cap-like part of which bears the mandible and 

 encloses the muscular apparatus. The frontal areas of the two rows of 

 zooecia meet at obtuse angles; the radical fibres, given off from and 

 ending in a chamber connected with the vibraculum, form parallel 

 connecting threads between the neighbouring branches Canda Lamouroux. 



4) The ooecium not enclosed in an avicularium ; the frontal areas 

 of the two rows of zooecia on the same level; the radical fibres form 

 no parallel connecting threads between the neighbouring branches . . . Scrupocellaria 



van Beneden. 



1) No vibracula: 



