Sponges from South Australia. 283 



Returning to the first family, viz. the Chalinida, it might 

 be observed that this was, as before noticed, the name given 

 by Dr. Grant to the third order of his PORIFERA (Tab. View 

 An. Kingdom, 1861, p. 76, Walton and Maberly) for the 

 purpose of including sponges " possessing the structure of 

 Johnston's Halichondria oculata^^ which is our Chalina poly- 

 chotoma ■= Spongia ■polychotoraa^ Esper, = Chalina oculata, 

 Bk. ; and it may also be observed in the " Key to my Clas- 

 sification of the Spongida" [Op. etloc.cit. p. 193) that I 

 have given this as the type of group No. 1, viz. the '' Digi- 

 tata," whose " typical structure/' to which I have before 

 alluded only in a general way, may be more particularly 

 stated as follows : — " A stipitate bunch of caulescent cylin- 

 drical stalks, more or less ramosely dividing dichotomously 

 and polychotomously, more or less interaniting on their way 

 to their termination in rounded ends. Easily yielding to 

 pressure, but still very resilient. Colour, when dry, light 

 sponge-yellow, often retaining traces of purple, which appears 

 to be its original colour, at all events in many instances. 

 Surface uniformly smooth, which is not the case in the EcHlisro- 

 NEMA. Vents chiefly in single lines, opposite to each other, 

 on each side of the cylindrical stalk. Structure internally 

 open, where the sarcode, which is very thin (as Ellis noticed), 

 has disappeared, as is usually the case in dried specimens ; 

 more compact towards the surface, where the dermal struc- 

 ture is finer and closer than that which is below it. Fibre 

 predominantly keratose ; spicule acerate, curved, fusiform, 

 smooth, sharp-pointed, variable in size, which is chiefly small, 

 often minute. General form also variable." 



As regards the latter character, viz. the variability in form, 

 I cannot do better than refer the reader to Miklucho-Mac- 

 lay's paper (M^m. de I'Acad. de St. Petersb. vii. s. t. xv. 

 no. 3, 1870) on the varieties of his " Veluspa yolymorpha^'' 

 which is an estuary specimen of Chalina polymorpha^ as may 

 be seen by reference to the typical form (Taf. i. fig. 1), among 

 which the Baikal freshwater sponge Lubomirskia haikalensis, 

 Pallas, is introduced as No. 11 (Taf. i. fig. 5). 



This brings us to the consideration of the specimens of 

 Rhaphidonema in Mr. Wilson's collection from the neigh- 

 bourhood of Port Phillip Heads, Victoria Col., S. Australia, 

 which, although very numerous, belong to only three groups : 

 viz. the Digitata, the Tubulodigitata, and the Bivalvata 

 respectively, but mostly to the first, under which Chalina 

 polychotoma and its varieties will presently be menticraed, fol- 

 lowed by a single species of Tubulodigitata and the same of 



