462 JANE STEPHENS : ATLANTIC SPONGES 



those of the spicules taken directly from the specimen of Polymastia, as would be 

 the case if they had long been separated from the parent sponge. In those parts of 

 the sponge where the Polymastia spicules make up a large proportion of the 

 skeleton, the transverse fibres usually contain only one row of oxea, and the main 

 fibres often contain only two or three rows. With the exception of a large 

 dichotrisene and one or two anatrisenes, the only foreign spicules seen in this part 

 of the sponge were those belonging to Polymastia. In the upper parts of the 

 sponge the Polymastia spicules do not appear, but a few anatrisenes and long shafts 

 of probably other Tetractinellid spicules penetrate the sponge in various directions 

 or lie horizontally on the dermis. 



Halichondria panicea (Pallas). 



Coaling jetty at Cape Town Docks. 14th May 1904. 



Station 482. Reit's Bay, Saldanha Bay, shore. 21st May 1904. 



Station 483. Entrance to Saldanha Bay, 25 fathoms. 21st May 1904. 



The specimens of this almost world-wide species, collected off the coaling jetty at 

 Cape Town Docks, are growing on the living shells of mussels, and spreading over 

 sea-weed and over a large compound Ascidian. In places they are overgrown by 

 Plumularia echinulata, Plumularia setacea, and Plumularia pinnata. On the 

 shells they are growing in company with Reniera cinerea. 



The specimens dredged at the entrance to Saldanha Bay are spreading over 

 Myxilla simplex (Baer), or are penetrated by densely growing hydroid colonies. 

 The best preserved specimen is about 9 cm. across. The maximum size of the 

 oxea is about 0'5 mm. by 0'013 mm. 



Reniera cinerea (Grant). 



Coaling jetty at Cape Town Docks. 14th May 1904. 



Station 482. Reit's Bay, Saldanha Bay, shore. 21st May 1904. 



The specimens of this widely spread species, collected off the coaling jetty at 

 Cape Town Docks, are growing in soft, cushion-like masses on living shells of mussels 

 in company with Halichondria panicea. The largest is about 35 mm. in length. 

 One of the specimens is closely crowded with embryos containing numerous very 

 small and slender oxea. The specimens collected between tide-marks in Reit's Bay 

 are growing in small, rounded masses on Laminaria-like roots, together with 

 Halisarca dujardini. The oxea, which are arranged in a unispicular network, 

 are 0-135-0-15 mm. by 0"005-0-008 mm. 



This species, which has been recorded from the shores of the Arctic, North 

 Atlantic and North Pacific Oceans, is now recorded, apparently for the first time, 

 from the South Atlantic. 



