48 ART. 1. — I. IJIMA : HEXACTTNELLIDA, III. 



The dermal surface in all the specimens is smooth. In the 

 j)rofile edge of the body, there is seen a clear space right under 

 the dermal layer and separating this from the opaque choanosome ; 

 it is the relatively widely developed subdermal space. The surface 

 of the choanosome presents a spongy appearance on account of 

 the ill-defined, variously sized but on the whole small, apertures 

 to incurrent canals. The gastral surface is not covered with a 

 continuous gastral layer, l-ut there directly open excurrent canals 

 which may measure 1 mm. or more across in the larger sj)ecimens. 

 Such a small sjiecimen as is represented on the right of fig. 27 

 may, in the wet state, be said to be nearly translucent all over 

 excepting only the basidictyonal mass which appears whitish. 



None of my specimens is in a sufficiently good state of 

 preservation for a histological study. Nevertheless, thus much 

 could be determined, viz., that the trabecuhe are scantily and thinl}^ 

 developed both in and below the bounding surfaces, and that the 

 shape and arrangement of the chambers are much the same as 

 in L. orlhodocus. 



Spiculation. 



The iparencliymalia consist of oxyhexactins and diactins, the 

 latter occurring only very sparsely (PI. III., fig. 37). 



The parenchymal oxyhexactins may be said to be of a 

 moderately large size, tliough subject to much variation in this 

 respect. A large one may measure 4 mm. or moie in axial length 

 and about 13 <'■ in breadth of ray near the central node ; but 

 such large dimensions are attained by the spicule in question 



