STArROCALYPTUS RŒPERT. 169 



large (up to 8 mm. dia.l, sharply contoured, excurrent apertures 

 were freely open, i.e., not covered by endosome. The above seem to 

 constitute tlie more important macroscopic features of tlie species. 



As to the .^piculalioii, all the skeletal elements are remarkable 

 for their slenderness. 



The strongest ixirenchymal diactins seem not to exceed 35 !'■ 

 m lireadth. The ^''ai'enehymalia in general have sparsely micro- 

 tuberculated ends, the very tips being pointed. The smaller or 

 the more slender of them show kno1)S cruciately disposed around 

 the spicular center. 



The oxypentactinic hypodermalia have slender paratangentials 

 under 2 mm. in length and Vo f- in thickness at base; these are 

 smooth except at the rough outer ends and are not quite straight, 

 but rather wavy. — Besides the oxypentactins, strands of diactins 

 also serve to support the ectosome. These hypodermal diactins 

 are of various lengths ; they are all cruciately tubercled in the 

 middle. While those of çrreater leno-th are indistinsfuishaljle in 

 appearance from a parenchymal diactiu, the shorter ones may 

 equal the dermalia in axial length and may have rays exactly 

 similarly characterized as in the latter ; so that, such short diact- 

 ins, especially when in isolated positions, might as well be classed 

 under the dermalia as under the hypodermalia. The statement 

 therefore seems justifiable that the dermalia pass over l)y gradation 

 to the parenchymalia through the intermediation of hypodermal 

 diactins. 



The derma/la (PL XIV., figs. 30 and 31) are predominantly 

 pentactins, not infrequently stauractins and rarely monactins, not 



