E. IMPERIALIS. — SPICULATION. 69 



number with exactness. Lower down on the body, the counting 

 is however comparatively easy, as is also always the case with 

 the transverse beams throughout the entire length of the body, 

 these being everywhere relatively well separated. 



Spiculation. 



The parenchymalia prÎ7icipalia are large slender-rayed 

 oxystauractins, in which the longitudinally disposed axis is 

 usually much longer than the transverse. The former is straight 

 and in large specimens may attain a length of nearly 100 mm. 

 and a breadth of 180 /^ or over near the spicular center. The 

 shorter transverse axis may be 30 mm. long. The two lateral 

 rays of this axis are somewhat inwardly directed as they arise 

 from the center, so that they may enter into the composition of 

 the transverse skeletal beams, which are more innerly situated 

 than the longitudinal. Each point of intersection of the two 

 main systems of the skeletal beams is usually, though not 

 always, occupied by a single oxystauractin center ; but not infre- 

 quently it shows none of this. Since therefore the rays are very 

 much longer than the sides of the skeletal meshes, each beam 

 of the skeleton is supported by several oxystauractin rays. 



Along the inner border of the cuff, i.e., in the uppermost 

 transverse beam of the skeleton, the principalia take a different 

 form in that they are here usually provided with a short distal 

 ray which extends radially into the cuff!', while the superiorly 

 directed, longitudinal ray becomes abortive. 



The comitalia accompany the rays of the principalia in 

 profusion. They are nearly exclusively elongate thetactins of 

 quite a fine caliber. They may be 30 mm. long with a breadth 



