SECOND ADDENDUM 

 TO THE MONOGRAPH OF THE AUSTRALIAN SPONGES. 



By R. von Lendenpeld, Ph.D. 



Halme laxa. N. sp. 



Shape and Size. 



This sponge is similar to the digitate vai'iety of Holme nidus 

 vesparimi, but it grows to a much larger size. The central 

 bulbous mass measures 60 mm. in diameter, and is attached by a 

 base about 40 mm. wide. From this 5-10 or more digitate 

 processes grow upward. These attain a very much larger size in 

 the vai'iety digitata than [in the variety minima. The whole 

 sponge is, as the name implies, very loose in its structure. It is 

 hollow throughout, the wall on an average 10 mm. thick. This 

 wall is perforated by a great number of large holes which lie so 

 close together that only narrow bridges of sponge tissue are left 

 between them. The width of the meshes varies in the varieties. 

 The average width however, is never less than 10 mm., whilst 

 the thickness of the intervening walls does rarely exceed 1'5 mm. 

 The shape of the meshes is more regular in fresh specimens 

 than in dried ones, in consequence of the extreme laxity of the 

 whole structure. Nevertheless, even in the fresh state, the meshes 

 appear very much larger and more irregular than in any other 

 species. They are of uniform shape throughout the whole body of 

 the sponge. 



Surface. 



The surface is smooth, rendered slightly uneven in consequence 

 of the irregular curvatures of the sponge lamellse. 



