dredged up from the Gulf of Manaar. 143 



fig. 51, i), or by an interlocking, inseparable without fracture, 

 of the filigree of one branch with that of another (PL VIII. 

 fig. 48, kkk and I). At least I have not yet seen direct 

 union between the parts of one spicule with those of another 

 in a Lithistid. 



Although most of these Melobesian nodules present one 

 or more growths of Lithistida upon them respectively, yet it 

 is only in one or two instances out of the seven species that 

 I have found that two different ones have been observed on 

 the same nodule; while so abundant are they that it is hardly 

 possible to mount a fragment of any other sponge on the 

 nodule without finding in it spicules of a Lithistid. 



Of the "seven species" three may be termed " Coral- 

 listes" because they do not appear to commence their growth 

 in discoid elements ; while the opposite is the case with 

 the other four, which will be termed " Discodermia." Of 

 course, in describing and illustrating them, my observa- 

 tions will be confined to their structure, since they must be 

 regarded as only little growths or traces, as before stated, 

 of the entire sponges; while the illustrations, on the other 

 hand, must be considered as diagrams after nature, for 

 such is the intricacy of Lithistid structure that it is almost 

 hopeless to attempt any thing beyond catching the specific 

 character and representing this as near to nature as possible. 

 Having premised these remarks, we will begin with the 

 Gorallistes. 



CORALLISTES. 



Gorallistes acideata, n. sp. (PL VII. fig. 45, a, b.) 



Surface characterized by the presence of erect spike-like 

 processes (PL VII. fig. 45), which, when the structure is 

 torn to pieces, are respectively found to be supported on three 

 arms, which are tubercled and repeatedly subdivided into 

 branches until they end in a filigree consisting of minute 

 angular processes, which interlock with those of the neigh- 

 bouring spicules (fig. 45, a). Spike conical, elongated, sub- 

 sinuous, l-333rd long by l-120th inch in diameter at the 

 base, more or less cononodose, tubercles more or less in cir- 

 lar lines round the lower two thirds of the spike (fig. 45, a, b). 

 Internal structure composed of spicules of the usual Lithistid 

 form, consisting of four arms, each of which is repeatedly 

 divided and subdivided into branches until they end in the 

 way above mentioned. Size of largest specimen about \ inch 

 in horizontal diameter. 



Hab. Marine. On hard objects. 



Loc. Gulf of Manaar. 



