74 THE SPONGES OF THE WEST-CENTRAL PACIFIC 



their oscules there may be raised collars. When these collars are well de- 

 veloped, they come to resemble tubes. 



Haliclonid sponges occur that are principally tubular, with oscules only 

 at the summits of hollow cylinders. This form may be merely an exaggera- 

 tion of the oscular collars of Reniclona sponges; if so, the name Reniclona 

 may need to be replaced by Reniera. Such sponges, however, are here still 

 regarded as of generic rank. 



Reniera being ill known, Lendenfeld 1887, page 796, erected the genus 

 Phylosiphonia for these tubular sponges. One might argue that this name 

 should supplant Nardo's name, but it is here assumed, on the basis of 

 Schmidt's discussions, that Reniera is available. 



Reniera implexa (Schmidt) de Laubenfels 



Text Figure No. 44 



This species is here represented by the following: 

 U.S.N.M. No. 22981, My No. M. 358, collected July 5, 1949, by diver in the 

 south corner of the lagoon at Ebon Atoll, in a miniature lagoon. The 

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



There is a massive base, 3 cm thick and 5 cm in diameter, from which 

 hollow cylinders rise 2 or 3 cm higher. 



The color in life was lavender, with occasional patches of whitish drab. 

 The latter were probably moribund. The endosome had the same color as 

 the surface, and the consistency was very soft and fragile. 



The surface is micropunctiform with skeletal pores 160 p. in diameter. 

 Each such contains about seven actual pores which are 40 p to 60 p in di- 

 ameter. These are separated from each other only by narrow strands of 

 protoplasm about 10 /x to 20 p, wide. The oscules cannot be separated from 

 the pores by visual observation. 



There is no ectosome, and the endosome is an isodictyal reticulation. 



The skeleton consists of oxeas, 2 /x by 130 [x to 3 /x by 120 p in di- 

 mensions. 



This species was first described by Schmidt from the Mediterranean 

 region in 1868, page 27. Burton, 1930, page 515, records it from the Indian 

 Ocean; and Wilson, 1925, page 398, from the Philippines. It is probably 

 fairly common throughout the Old World but is not sharply separated from 



Text Figure No. 44. Two of the spicules (oxea) of Reniera implexa, X 781. 



