PorC-nren of Cliona corallinoidos. lo 



tlicm, a.-< rtV|uire(l — a prufos.s wliifli, of courso, i.s vrry slowly 

 eHV>et«'il, on nccvnint ot the auKvljoid iiatun' of the sarcodc ; so 

 that, on (loath occurriu;;; stuMonly (that is, where the sarcodc 

 has tiot become putrid and passed into dissolution, and there 

 has been no time for cli>sin_i; hy reflex action) these apertures 

 remain. Hence in dried specimens, where the dermal sarcodc 

 is not destroyed, they remain visihic. 



There are two kinds of openiiii^s, viz. the pores and the 

 vents — the inhalant and exhalant a[)ertures. 



Directin::^ our attention to the former first, we find tliem 

 averagin*]^ about a lOOOth of an inch in diameter, — cither scat- 

 tered "generally over the dermal sarcodc opposite the interstices 

 of the subjacent spicular structure, as in the Espcriada*, ILiU- 

 chondria jxinice'i, Johnston, v.^c., and the Calcispongia"! ; or 

 confined to circular areas in juxtaposition, as in liap/ii/rus 

 (rriffiffisu\ Bk. [Clionn cehifa?), liaphiojy/ioni patera ^ Qi-dyy 

 or Neptune's Cuj), Parhi/matisma^ Sec. ; or to circular areas 



separated from each other and raised on cylindrical heads, as 

 in Grat/ella cyatho2)hora, Cart., Cliona cor all ino ides ^ Hancock, 

 &c. 



Of these the Clionida?, including Eaphi/rus! and liaphiophora 

 (see " M(5ra. sur le Genre Puti'rion,^'' par P. Ilartiiig, Soc. dcs 

 Arts et des Sci. d'Utrecht, 1870, pi. 4. figs. 7 tt 12), present 

 examples of a division of the sponge-structure in the pore-areas 

 resembling the tentacular head of a polype ; but as this is 

 merely a resemblance, and my object in introducing the sub- 

 ject of the openings in the sarcode of the Spongiadai is more 

 especially to show this, I shall take Cliona corallinoides alone 

 (PI, II. fig. 33) for description and illustration, as affording 

 the nearest resemblance of this kind that I have met with. 



This sponge (like Pap/ii/rus Griffithsii and the great Nep- 

 tune's Cup, together with the diminutive Grantia ciliata 

 and its like among the calcareous sponges) possesses no 

 branched system of excretory canals like most of the other 

 sponges, but consists merely of an areolar structure (PI. II. 

 figs. 33 & 36, a a) which, burrowing between the layers of 

 univalve and bivalve shells, forms for itself therein similar 

 excavations, which open into each other by efferent (fig. 3G,ccc) 

 and afferent apertures, finally communicating with the exterior 

 by distinct heads (figs. 33, a, h, & 36, h) here and there, most 

 of Avhich are simple pore-areas (fig. 34), while the rest present 

 a combination of vent and pores (fig. 35) or a single large 

 vent only. Cliona corallinoides not only excavates shells, but 

 the sandstone rock too of this locality, where it shelters itself 

 under the florid expansions of Melohesia lichenoides^ which 

 goes on growing (that is, spreading in all directions), while the 



