530 EDITH M. PRATT. 



Zoochlorellae are present in that portion of the endoderm of the transverse canals which 

 lies nearest to the surfoce, but they are not numerous, few are to be found in the lumen 

 of the canals. 



Owing to the great amount of space occupied by the spicules the supply of mesogloea 

 is less abundant than in other species, but it is of a very dense nature and stains very readily. 



15. Sclerophytmn querciforiiie sp. nov. (PI. XXXI. fig. 33). 



Two complete colonies were taken in shallow water on Hulule, Male Atoll. Both 

 specimens are arborescent and are very similar in their manner of growth. Each is com- 

 paratively tall and slender, with a much branched capitulum, many of the branches having 

 long and slender lobes. From near the base of the larger specimen a second stalk grows 

 out bearing a small branched capitulum (fig. 33). 



The larger colony is 46 mm. high. The stalk is cylindrical above the junction of the 

 secondary stalk and elliptical in cross section below. At the top the stalk is branched and 

 passes almost imperceptibly into the capitulum, which is 20 mm. high and 25 x 18 mm. in 

 diameter, being slightly compressed laterally. The branches vary very considerably in size, 

 but the two principal branches are 10 and 12'5 mm. long and about 4 mm. broad. The 

 lobes are very slightly flexible. The surface of the capitulum and stalk is granular and 

 fairly hard to the touch, but yields to slight pressure. The specimens in spirit were of a 

 pale greenish-grey which gradually changed to a deep cream colour. 



The spicules are very similar in form and structure to those of other species. Clubs 

 are very numerous near the surface, '2 — "26 mm. long by about "008 mm. in greatest breadth. 

 The tuberculate spicules vary in size, the largest being fully 6 mm. long by 1 mm. broad. 

 A few forked spicules occur but are not numerous. 



There are no siphonozooids in this species. 



The autozooids are fairly numerous and are all of one kind. Most of them are com- 

 pletely retracted. An autozooid cavity is '4 — "5 mm. in diameter just below the surface. 

 The tentacles are very short and pinnate. The pinnules are proportionately longer in this 

 than in any other species in the collection. 



The stomodaeum is long ; the siphonoglyph is well-marked and is provided vfith very 

 long cilia. The mesenteries are all strongly marked and are all provided with mesenterial 

 filaments; the dorsal mesenterial filaments are long, grooved and ciliated as in other species. 

 The ventral and lateral mesenterial filaments are not so long nor so broad as the dorsal 

 filaments ; they are more or less rounded in cross section and are similar in form and 

 structure to those of Sc. palmatuni, capitale, hirtum, and of many other Alcyonaria, but both 

 mesenteries and filaments are longer and broader than in many species of the genus. 



Canal Systems. The vessels of the superficial system are not so large nor so numerous 

 as in other species in the collection. The transverse vessels lie about "25 mm. below the 

 surface and have no vertical caeca, but follow a course almost parallel with the surface. 

 As in other species, these vessels communicate with the coelenteric cavities of the autozooids 

 and with many vessels of the internal system, which is very similar to that of other species, 

 but less strongly marked. 



Zoochlorellae are fairly numerous in the endoderm and lumen of the canals and in the 

 endodermal tissues of the autozooids. 



