PROK. THOMSON AND MR. McQlKEK REPORT ON THE ALCYONARIANS. Ill 



darker red patches where the nodes shine through the semi-transparent 

 coeneneh3-ma. The living colonies were pink. 



The calcareous internodes vary from 10 mm. to 17 mm. in length, and are 

 about 2 mm. in diameter They are marked longitudinally by sinuous 

 furrows which expand at intervals into little round pits. The colour o£ the 

 axLs shades from deep rose-red to pink. 



Fig. 3. 



Fig. 4. 



--o.:^-^ 



Clathraria acuta, Gray. 

 Fig. 3. Spicules. Fig. 4. Details and ornament on calcareous joints. 



Microscopic examination shows that the axis is composed of numerou.« 

 spindles fused together, with their long axes in line with the long axis of the 

 branch. The nodes are dark red, much shorter than the internodes, and 

 slightly swollen ; they are composed of a yellowish horny network enclosing 

 short red spindles. 



The pinkish-white coenenchyma is semi-transparent and very delicate. 

 The polyps are not nearly so numerous as in C. ruhrinodis, but are larger in 

 proportion and project from the surface as minute warts. They seem to 

 correspond in position to the cup-shaped pits in the axis of the internodes, 

 and their arrangement is very markedly spiral. 



The spicules of the ccEnenchyma are spiny and tubercalate clubs and 

 warty double-clubs with a few spindles and boomerangs. They are, on 

 the whole; rather smaller than in C. rubrinodis and distinctly less spiny. 

 The majority are colourless, but many show a red or pink tinge. 



f.ocality. — Khor Dongola, near the group of Islets; rock bottom, 9^ fathoms. 



[71] d 



