BY K, VON LENDENFELD, PH.D. 571 



Locality ; East Coast of Australia, Port Jackson. 

 This sponge is represented in fig. 20. 



Dactylochalina reticulata. Nov. spec. 



Digitate processes irregular, repeatedly branched and anasto- 

 mosing, 12 mm. thick, more or less cylindrical, with an uneven 

 surface, and much curved. Tapering at the tips to a pointed 

 terminus. Length of the sponge 200 mm.. Oscula large, scattered 

 over the surface. 



Locality : East Coast of Australia, Port Jackson, 

 This sponge is represented in fig. 22. 



When working out the sponges I was so deluded by the external 

 similarity of these sponges, as actually to put Chalinopsis imitans 

 and Dactylochalina cylindrica, and also Chalinopsis dichotoma and 

 Dactylochalina reticulata specimens together. Only afterwards I 

 ascertained by examining sections of different specimens under the 

 microscope, that I had confounded sponges belonging to two 

 different orders with one another. 



All the representatives of my sub-family Chalinopsinae of the 

 family Spongidse, are more or less similar to species of Chalinidse- 

 Monactinellid sponges. The most striking similarity however, is 

 shown by the four species described above. 



The similarity could be accounted for in various ways. We 

 might assume that the Chalinopsidse where the links connecting 

 the Ceraospongia with the Monactinellidse. In this case we would 

 have to assume that either the horny sponges have descended from 

 the silicious, and that the Chalinopsinse were horny sponges which 

 had been just produced by the loss of the silicious spicules in the 

 fibres of the similar Chalinidee, or that vice, versa the Chalinidte are 

 descended from horny sponges, and that these forms are the ones 

 just commencing to obtain spicules. - We might also assume that 

 these sponges were not at all related with each other. 



I have some years ago advocated the view, that silicious sponges 

 descended from horny ones, the evidence however, which has since 

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