57 



Tylostyles slender. 



Tylostyles stout. 



1 ntermediate. 



Of all these I possess camera-drawings at the same scale. This collection clearly showed me 

 the impossibility of a separation on account of the tylostyles. The specimens of the third list in 

 fact form all desirable transitions. Of course it was impossible to have all these drawings reproduced 

 and I therefore took only some samples. My original drawings and preparations are however at 

 the disposal of any spongiologist, who wishes to convince himself of the truth of my statement. 



SIBOGA-EXPEDITIE Vla'. 



