522 REVISION OF THE AXIXELLID.E, ii., 



the purpose of the present description, six specimens, four of 

 which, well preserved in alcohol, are from the original locality, 

 while the other two are washed-out beach-specimens obtained in 

 the vicinity of Port Jackson; examination was also made of a 

 mounted section of one of the type-specimens. As the possibility 

 of a mistake regarding the identity of tlie species was out of the 

 question, and, moreover, as the available specimens presented a 

 greater range of variation than that recorded in the case of the 

 original specimens, the latter were not sent for to be consulted. 

 The two specimens from the northern locality differ slightly 

 from the Port Phillip ones (more especially in certain details of 

 spiculation), but not sufficiently, I think, to warrant their being 

 regarded as constituting a distinct variety. In order briefly to 

 distinguish the specimens, the former are referred to in the 

 description as the P.J. specimens, the latter as the P.P. or typical 

 specimens. 



External features . — The typical habit of the species, so far at 

 least as regards the shape and mode of disposition of the branches, 

 is that displayed by thespecimen illustrated in PI. xxxiii., fig. 1 — 

 the largest and most profusely branched of those before me, 

 measuring 180 mm. in total height —which may be very satis- 

 factorily described, in the precise terms of the original descrip- 

 tion, as "consisting of a bushy bunch of rather slendei', short, 

 subcylindrical or somewhat compressed branches, sometimes 

 anastomosing, and supported on a short stalk." But in two 

 respects this specimen is perhaps exceptional : namely, in the 

 great multitude and closely crowded arrangement of the branches 

 (the number of which exceeds two hundred), and, secondly, in 

 possessing oscula which in comparison with those of other speci- 

 mens are conspicuously noticeable. In the four P.P. specimens 

 available, the branches vary from 5 to 8 mm. in stoutness, and, 

 except when somewhat compressed, are usually nearer to the 

 latter figure than the former; but in the P.J. specimens, in tlie 

 case of which also the stalk is comparatively long and narrow, 

 they are slenderer, 3 to 5 mm. in diameter, and much more 

 uniformly cylindrical (PI. xxxiii., fig.3). B)-anching takes .place 

 chiefiy, if not entirely, by dichotomy, and successive dichotomien, 



