SPONGELIA. 207 



Spongelia elastica, F. E. Schulze. 



Sponr/elia pallescens, subspecies elastica, F. E. Schulze, " Uutersuchungen iiber 

 dea Bau und die Entwicklung der Spongien. — VI. Die Gattuug Spongelia" 

 Zeitschrift fiir wissenschaftliche Zoologie, Band xxxii. Seiteu 150, 154 

 (1879). 



(Otber synonyms will be found below in the description of the variety.) 

 The different varieties of this species differ to a great extent in shape. S. e. 

 massa is incrusting or massive, horizontally expanded, cake-shaped, without 

 processes of any kind, whilst S. e. lohosa is erect, attached by a narrow base, 

 and generally possesses lobose processes which arise from the upper surface. 

 S. e. stellidermata is a long and narrow flabelliform sponge, which thins out 

 towards the serrated margin. The surface is covered with conuli l"5-3millim. 

 high, which are l"5-3*5 millim. apart. The conuli are smaller and closer 

 together in S. e, massa than in the other two varieties. The oscula are 3-10 

 millim. wide, scattered over the upper surface in S. e. massa, confined to the 

 summits of the lobes in S. e. lohosa, and arranged in a row along the margin in 

 8. e. stellidermata. The colour of the living sponge is greyish blue in S. e. 

 massa, brick-red in S. e. stellidermata, and violet in S. e. lohosa. The dry skele- 

 tons of all the varieties are Light greyish brown, pretty soft, compressible, and 

 elastic; but S. e. massa appears more elastic than the other varieties, and 

 approaches in elasticity the bath-sponge. 



The slceleton consists of knotty main fibres, 0*2 millim. thick, which are 1"5- 

 3 millim. apart. They are closer together in S. e. massa than in the other 

 varieties, and appear as columns of pretty densely packed large foreign bodies, 

 which are cemented by a small quantity of spongin. The connecting-fibres are 

 0'04-0-06 millim. thick, and mostly free from foreign bodies. They are 

 generally much branched, and anastomose to form a network with irregular 

 meshes, on an average 0'2 millim. wide. Only in the tubular parts of the 

 sponge the connecting-fibres appear more simple. Here they are often un- 

 branched, and the meshes between them squax'e. The skeleton-net does not 

 pervade the whole of the sponge in a uniform manner, but appears, particu- 

 larly in S. e. lohosa, confined to the septa of more dense tissue, 1-3 millim. thick, 

 which divide the lacunose tracts from each other. These are often situated 

 radially, and so the skeleton attains a somewhat honeycomb-Uke appearance, 

 which is particularly well developed in the Australian specimens of this variety. 

 In some of the Adriatic specimens, for which 0. Schmidt established the species 

 Spomjelia jjierforata, similar but more irregularly arranged askeletous lacunose 

 tracts are observed. The subdermal cavities are pretty highly developed ; the 

 ciliated chambers are rather irregular, sac-shaped, on an average 0'08 millim. 

 lonof and 0*06 millim. broad. The final ramifications of the inhalant canals are 



