NORTH ABIERICAN PORIFERiE. PART 11. 537 



in SponrjeUa Farlov'd, and the aspect of the svn-ftxce rougher. The hicurrent orifices are 

 not specially distinguishable in the skeleton, owing to the fact that the connecting tissue 

 does not so unifoi'mly fill up the cells formed by the primary and secondary fibres. The 

 excurrent orifices are about a line only in diameter, much smaller than in Farlovii, and 

 irregularly peppered over the surface. 



Loc, Phillip's Island, off Port Phillip's Head, Australia, in Soc. Coll. 



Variety tenuis. One specimen (PI. xv, fig. 13) has a slightly coarser skeletal texture 

 than irregularis, and the form is regular and vase-shaped. The external surface is pitted 

 and seamed by deep depressions. The internal surfiice is pierced by numerous excurrent 

 orifices of small size. The primary fibres project but very slightly, and the whole is re- 

 markably smooth. Another sjDecimen of this variety existing in the Philadelphian collec- 

 tion has a similar form, but the outside of the cup is supplemented by two incomplete vase 

 forms, budding from the base. Another specimen has a vase-shaped form, with a skeleton 

 not quite so dense as in the fii'st, but still very closely approximates to the same condition 

 and surface, with precisely the same characteristics in the interior, where it was in perfect 

 preservation. 



Loc, Phillip's Island, Australia, in Soc. Coll., and near Sydney, New South Wales, in 

 Acad. Nat. Sc, Philadelphia. 



Variety erecta. This variety differs somewhat in the texture of the skeleton from tenuis. 

 It is not quite so coarse, but it otherwise resembles it quite closely. The shape (PI. xvii, 

 figs. 12, 13) is quite distinct, being almost fistulose, and the exterior very deeply pitted. 

 The inside of the cup is very shallow. 



Loc, Phillip's Island, Australia, in Soc. Coll. 



A specimen in the Collection of Peabody Academy from Swan River, Australia, is a tall, 

 pedicellated, flabellate form, with numerous orifices on the upper edge. These, as in 

 Spomjelia densa, correspond to ridges which follow the directions of the internal channels. 

 This form and these ridges give considerable similarity to Spongelia densa, but the skeletal 

 structure is distinct, and like that described above. 



Spongelia palmata Hyatt. 



This species (PI. xvii, fig. 15) is remarkable for the looseness and fineness of the skeletal 

 structure. The form in the variety figured is flabeUate, with a broad and very flat pedicle. 

 The U2)per edge is, as usual, occupied by the excurrent orifices. There are ridges running 

 from these and corresponding to the excurrent canals, but they are not very prominent. 

 The texture is so loose that the light shines through all parts excejit the extreme lower 

 part near the pedicle, where the tissue becomes very dense and hard. The primary fibres 

 are not so coarse as in Sjiongelia Farlovii, but much more widely separated, and the con- 

 necting tissue of secondary fibres has a much larger and more irregular mesh. There is 

 no appearance of net-like connecting fibres, and the tissue is so irregular that it is difficult 

 to detect on the surface the usual polygonal cells of the genus. 



Loc, Pacific Ocean, U. S. Ex. Exp., in Yale Coll. 



Two other specimens, one in Coll. Acad. Nat. Sciences, Philadelphia, and one in the Soci- 

 ety's Collection, agree with the description given above very closely, but there is a consid- 

 erable variation in the surface. The largest is a foot broad by nine inches in height, and 



MEM0IB3 BOST. SOO. KAT. HIST. VOL. H. 135 



