216 



THE SPONGES OF THE WEST-CEXTR.il. PACIFIC 



U.S.N.M. No. 22978, My No. M. 354, collected July 5, 1949, by diver from 

 the Pearl Pool in the western portion of the lagoon of Ebon Atoll. The 

 depth was 2 meters, and the substrate was dead coral. 



U.S.N.M. No. 22998, My No. M. 376, collected July 7, 1949, by diver from 

 the ocean at the west side of Ebon Atoll, near Rube point, at a depth of 

 4 meters. The substrate was dead coral. 



U.S.N.M. No. 22818, My No. N. 025, collected August 21, 1947, by F. M. 

 Bayer and F. C. Zimmerman, from the reef of Rongerik Atoll near 

 Latobak Islet in coral of the species Stylophora mordax. At the same 

 time they collected two other very similar specimens — my numbers N. 

 021 andR 028. All three are in U.S.N.M. Accession No. 176603. 



Members of the family Clionidae bore into any submerged calcium 

 carbonate. On the Pacific Islands, it is usually dead coral that is inhabited. 

 To find Cliona one must, as a rule, break the coral into small pieces or dissolve 

 it with acid. Therefore, it is very difficult to observe the actual abundance of 

 boring sponges, but my field work left me with the strong impression that 

 Clionidae were comparatively rare in the Western Pacific. Certainly, there was 

 not the conspicuous abundance of them which is obvious in many portions of 

 the West Indies and of the Atlantic Coast of North America. 



The Clionas which here are identified as lobata were often found to have 

 communication with the outer world by means of openings at the surface of 

 the branches of coral, which openings were about 1 mm in diameter and 1 cm 

 apart. The specimens from Ebon Atoll were all restricted to small but exceed- 

 ingly abundant galleries in the coral. All the other specimens here included 

 showed exceptionally large single masses in the center of the branches of 

 coral — masses of sponge tissue 4 to 6 mm in diameter, and indefinitely long. 



The color in life was bright yellow, and the consistency was soft. 



The surface and the pores and oscules are obscured by the boring habitus. 



A (, 





Text Figure No. 147. Spicules of Cliona lobata, X 782. A and B: Tylostyles; in each 

 case the entire spicule shows, but in two parts. C : Two of the spirasters. 



