72 RECORDS OF THE AUSTRALIAN MUSEUM. 



or four diameters of the extremities, thence tapering rapidly to 

 acute points. Size — 0'16 by 004 to 006 mm. 



There are seven specimens from Tuggerah Beach, four from 

 Swansea, and three from the Hawkesbury River. 



Chalina palmata, Lamarck. 



Chalina palmata (Lamarck), Ridley and Dendy, Chall. Rep., Zool., 

 XX., 1887, p. 26, pi. v., fig. 4. 



Cladochalina euplax, Lendenfeld, Zool. Jahrb., ii., 1887, p. 769, 

 pi. xxvii., fig. 26; id., Aust. Mus. Cat. xiii., Sponges, 1888, 

 p. 85. 



Sponge variable in habit, occurring in roundish clumps, with 

 several points of attachment, either palmate, tiabellate, digitate, 

 or half cup-shaped, with digitate or subfiabellate branches along the 

 margins, which generally exhibit dichotomous division. The outer 

 surface is usually concave, and the inner convex. The oscula are 

 mostly confined to the inner surfaces. In well preserved specimens 

 the margins are thin, even, and slightly elevated; in worn examples 

 they are irregularly substellate. Colour when alive, drab or dark 

 slate ; beach-worn examples vary from sandy yellow to dark rusty 

 brown. The spicules are slightly curved oxea ; they occur in the 

 ground substance as well as in the fibres. Size — 0-07 by '0024 mm. 



There are twenty-five specimens from Tuggerah Beach, three 

 from the Hawkesbury River, and two from Swansea. 



Chalina finitima, Schmidt. 



Chalina finitima, Schmidt, Grundzuge einer Spongien-Fauna 

 Atlantischen Gebietes, 1870, p. 33. 



Acervochalina finitima, Ridley, Zool. Coll. "Alert," 1884, p. 399. 



Ceraochalina finitima, Lendenfeld, Zool. Jahrb., ii., 1887, p. 

 781. 

 This is probably the most common sponge occurring on the 

 coast. There is one specimen in the Lendenfeldian collection 

 which bears the manuscript name of Cladochalina irregularis, 

 Lendenfeld (No. 323). The sponge generally consists of a pair 

 of irregular, elongated, subfiabellate expansions, more or less con- 

 nected at their inner bases. Occasionally the intervening spaces 

 between the thick lamellse are filled in with fibre, leaving two long 

 ridges with a more or less distinct valley between. The height 

 rarely exceeds 100 mm., whilst the length is often over 200 mm.; 

 the thickness varies between 10 and 20 mm. The oscula are from 

 1 to I mm. in diameter; they are abundant on the upper inner 

 aspect of the often truncated margins, and are also present on the 

 inner surfaces, rarely on the outer ; frequently they occur on the 

 inferior borders of the lamina. The spicules are very slender 

 hair-like oxea, measuring 0-1 by 0*0018 mm. 



