CHAÜNOPLECTELLA CAVERXOSA. 



69 



frequency it occurs in the nut-sized inclividiial of fig. 8 in the 

 same plate. And in all still larger specimens it occurs very 

 commonly. . In fact, it is at least the predominant, if not the 

 only, discohexaster-form to be seen in the parenchyma of all 

 full-grown specimens. It is usually most abundantly found among 

 the beams of the gastral layer where it is often seen in patch- 

 like congeries. 



The following table may serve to show the relative proportion 

 in which the three above- described discohexaster-forms occur in 

 differently sized individuals of the species : 



The above data seem to allow the following general observa- 

 tions to be made. In an early stage of the sponge's growth the 

 discohexasters are mostly of the form a, only a few of the form 



