142 



1) The colony jointed, the two inner zooecia in each bifurcation 

 being divided into a distal and a proximal calcified portion, connected 

 by a chitinous tube; the vibracula far from reaching the central suture 

 of the branch. (The cryptocyst occupying about one-fourth of the whole 

 length of the zoa^cium. The proximal margin of the vibraculum sei)a- 

 rated from the distal wall on the jjroximal side of it by a distance 

 which is at least half as large as the breadth of this wall; not in- 

 frequently avicularia along the middle of the branch; no opercular 

 spine) C. arachnoUes Lam. 



1) The colony not jointed; the vibracula almost reaching or sur- 

 passing the central suture of the branch ; 



2) The zooecia with a hammer-shaped ojjercular spine; the proximal 

 margin of the vibraculum is separated from the distal wall by a dis- 

 tance which is about half as large as half the breadth of the latter; 

 the vibraculum almost reaching the central suture of the branch; 

 the cryptocyst is a little shorter than half tlie lengtli of the zo(r- 



cium C. retiforinis Smitt '. 



2) No opercular spine; the proximal margin of the vibraculum 

 almost reaching the distal wall; the vibraculum reaching or surpassing 

 tiie central suture of the branch; the cryptocyst occupying about one- 

 third of the whole length of the zouicium C. caraihica n. sp. 



? C. simplex Busk'-. 



V C. tenuis M. Gill.l 



On account of the remark made l)y Husk", that the avicularia in the sutural 

 line of the branch in C. arachnoides do not seem Id be developed in connection 

 with the separate zocrcia, I may here call attention to the fact that Husk is 

 wrong in his supposition. On splitting a branch into its two lateral halves it will 

 easily be seen that lliese strongly compressed avicularia are given off from the 

 free continuation of the inner lateral nuugin of the zoa^cia. 



Rhabdozoum Wilsoni Hincks, 

 Annals Nat. Hist. V Ser., Vol. X, pag. 160, PI. VIII, fig. 4. 



This peculiar form, of which I have been able lo examine specinuMis from 

 Western Port and Port Phillip, Victoria, which I owe to the kindness of Mr. J. 

 Gabriel and Miss Jelly, is by Hincks wrongly referred to the Eiicniliidac, a 



' 102, p. 16. - 8, p. -JG. ' (i8, p. 107. 



