104 TUNICATA. 



radiating lines, or irregularly; mouth toothed or emarginate; inter- 

 tubular surface cancellous. 



90. D. hispida, Johnston, I.e., p. 268. Polyzoarium adnate ; cells 

 in radiating lines with two to four long teeth round the mouth. 



ORDER PHYLACTOL^MATA. 

 Lophophore bi-lateral ; mouth with an epistorne. 



Sub-Order Lopliopliea. 

 Arms of lophophore free or obsolete. (Fresh water.) 



FAMILY PLUMATELLID^E. 

 Polyzoarium rooted. 



PLUMATELLA. 



Polyzoarium confervoid, branched, composed of a series of mem- 

 brano-corneous tubular cells, each of which constitutes a short ramulus 

 with a terminal orifice ; branches distinct from one another. Lopho- 

 phore crescentic, with two long arms. 



Europe. North America. Australia. 



91. P. aplinii, ftlacgillivray, Trans. Royal Soc. Vic., I860, p. 204. 

 Polyzoarium adherent, creeping ; cells cylindrical, with a distinct keel ; 

 aperture oblique. 



Homebush Creek, Malvern Hills, under stones. Australia. 



I have only examined dried specimens, but Macgillivray says that 

 the tentacula are about sixty, and the statoblasts elongated. It 

 approaches very near to P. emarginata of Europe. 



Class Tunieata. 



Alimentary canal suspended in a double walled sac, not capable of 

 protrusion, mouth opening into the bottom of a respiratory sac ; animal 

 simple or composite ; an imperfect heart in the form of a tube open at 

 both ends. 



Marine. 



FAMILY ASCIDIID^;. 



Animal simple, fixed ; solitary or gregarious ; oviparous; branchial 

 sac simple or disposed in (eight to eighteen) deep and regular folds. 



ASCIDIUM. 



Sessile, covered with a coriaceous or gelatinous tunic ; branchial 

 orifice 8-lobed, furnished inside with a circle of simple tentacular fila- 

 ments ; anal 6-lobed ; branchial sac not plaited, its meshes papillated. 



Greenland. Europe. North America. 



1. A. erythrOStoma, Quoy, I.e., iii., p. 609. Transverse, 



