dredged up from the Gulf of Manaar. 133 



through the stratum of siliceous ovaria (globules)," I 

 think that, although the locality, being not known, may be 

 different, there can be no doubt that the Manaar specimens 

 are identical with it in species ; and therefore I have used 

 Dr. Bowerbank's name. The minute acerate dermal spicule 

 to which he alludes I have not seen. 



Geodia areolata, n. sp. (PI. VI. figs. 36, a-g } and 37.) 



General form globular. Colour now light cinnamon exter- 

 nally. Surface more or less regularly areolated by lines of 

 minute echinating acerates fixed by one end in the dermal 

 sarcode, otherwise charged with minute stellates and closely 

 applied to the subjacent petrous crust, one of whose holes 

 may frequently be seen in the centre of the areolar interstice 

 (PI. VI. fig. 37). Pores minute and numerous in the dermal 

 sarcode, giving it a cribriform structure. Vents in groups, or 

 scattered here and there singly. Internal structure consisting 

 of the usual kind of spiculation distributed throughout an 

 areolar sarcode, more confused and compact towards the 

 centre, but presenting no defined nucleus. Spicules of eight 

 forms, viz. : — 1, the zone-spiculc, with trifid head expanded at 

 nearly right angles to the shaft, 200 by 5-1800ths, head 

 40-1800ths in diameter (fig. 36, a) ; 2, large, smooth, fusi- 

 form, acerate, curved, 150 by 3-1800ths (fig. 36, b) ; 3 and 

 4, fork and anchor, arms respectively about 5-1800ths long 

 (fig. 36, e) ; 5, siliceous globule, 21 by 16-6000ths (fig. 36, 

 d) ; 6 and 7, external and internal stellates respectively, the 

 former l-6000th and the latter 4-6000ths in diameter (fig. 36, 

 e,f), in form much the same as in the last species; 8, minute 

 dermal acerate, 60-6000ths long (fig. 36, g). Spicules ar- 

 ranged in the usual way, viz. the heads of the zone-spicules 

 spread out in the inner part of the petrous crust, which is 

 l-35th inch in thickness. Size of largest specimen about an 

 inch in diameter. 



Hab. Marine. Free or attached to hard objects. 



Loc. Gulf of Manaar. 



Obs. This chiefly differs from the last species in the areo- 

 lated form of the dermal layer, arising from the presence of 

 reticulated lines of minute echinating acerates, its contact 

 with the petrous crust, the form and position of the heads of 

 the zone-spicules, and the cinnamon colour externally. 



Geodia ramodigitata, n. sp. (PI. V. fig. 31, a-f.) 



General form cylindrical, digital, occasionally branched 

 (PI. V. fig. 31). Colour grey. Surface (which is much worn) 



Ann. & Mag. N. Hist, Ser. 5. Vol. vi. 10 



