SPONGES FROM COASTAL BEACHES OF N. S. WALES — -WHITELEGGE. 95 



Leiosella silicata, Lendenfeld. 

 Leiosella silicata, Lendenfeld, Proc. Linn. Soc. N.S.W., x., 1886, 

 p. 545; id., Aus, Mus. Cat., xiii.. Sponges, 1888, p. 122 ; id., 

 Men. Horny Sponges, 1889, p. 215, pi. xii., fig. 1, pi. xx., 

 figs. 12, 13, 16, pi. xxi., fig. 3. 



This species is frequently washed up on our coastal beaches 

 after heavy gales. There are four examples: two from Lake 

 Illawarra and two from Tuggerah Beach. 



The type specimen is evidently only a young form or a fragment, 

 judging from the examples now under notice. The measurements 

 of the type are 70 ram. in length, 40 mm. in breadth, and 20 mm. 

 in height. A specimen from Lake Illawarra is 100 mm. in height, 

 224 mm. in length, and 180 mm. in breadth. The sponge consists 

 of a series of lamellre, from 5 to 15 mm. thick, generally forming 

 irregular cups, which vary in size from a few mm. in depth and 

 width to 100 or more mm. The margins of the cups are thick, 

 and either rounded or truncated, with numerous depressions, like 

 such as would be produced by pressure from the tips of fingers, 

 depressions of the same kind occur more or less on all parts of the 

 surface. The line of coalescence between two or more cups is 

 usually distinct, depressed, and marked by numerous vent-like 

 openings, generally under 1 mm. in diameter. Similar apertures 

 are scattered over the whole surface, but they are better defined 

 on the outer aspect of the walls. The secondary fibres exhibit a 

 single axial row of regularly arranged spicules of many kinds. 

 The texture is like that of the finest bath sponge, soft and velvet- 

 like to the touch. 



EusPONGiA, Bronn. 



EusPONGiA IRREGULARIS, var. SILICATA, Lendenfeld. 

 (Plate xii., figs. 17 - 17a). 

 Euspongia irregularis, var. silicata, Lendenfeld, Proc. Linn. Soc. 

 N.S.W., X., 1886, p. 495; id., Aust. Mus. Cat., xiii., Sponges, 

 1888, p. 134; id., Mon. Horny Sponges, 1889, p. 225, pi, xiii , 

 fig. 1, pi. xxi., fig. 10. 

 This variety is very common on the coastal beaches, and attains 

 to a very large size. The description, as given in the Monograph 

 of Horny Sponges, is not sufliciently accurate — as regards the 

 larger specimens — for identification. The contents of the fibres 

 are not correctly described, if the single spirit specimen (No. 54) 

 in the Lendenfeldian collection is rightly named. 



There are seven well grown examples in the Fisheries' donation, 

 and very many others on exhibit and in the duplicate collection. 

 These are, however, all beach-worn to some extent, and present 

 characters not evident in the small spirit specimen. 



The sponge, in its young state, is often massive, higher than 

 broad, with incipient vertical lamellae in the form of strongly 

 developed ridges. In well grown adult specimens the sponge 



