298 



Lengtli of pro-rachidial margin of largest pinnule . 24 mm. 

 Breadth of insertion of largest pinnule . . . 10 mm. 

 Breadth of largest pinnule . . . . .16 mm. 

 Distance between pinnules . . . . .25 mm. 



The stalk is slightly conical with a swelling at the base of the rachis. Both 

 the meta-rachidial and the pro-rachidial surfaces of the keel are free throughout 

 their entire length. On the meta-rachidial surface the pinnules almost meet at 

 the upper end but leave a heart-shaped space at the base. The pinnules are 

 disjjosed laterally, but at the lower end they suddenly approximate towards the 

 pro-rachidial surface, so as to enclose a boat-shaped area with a long elliptical 

 keel. They are fan- to sickle-shaped, fairly thick and opaque. The zooid-plate 

 is marginal and extends well into the polyp region. No trace of a zooid-streak 

 could be found. The polyps are disposed in five to six it)ws on both surfaces 

 of the pinnules. Numerous large ova are seen attached to the mesenteries 

 which extend almost to the base of the pinnules. There are a number of long 

 limy needles in the polyp region. The rays are not very strong ; they project in 

 some cases 2 mm., but this is by no means regular. 



Locality : Unknown ; No. M/--- (Dr. J. Anderson). 



Previously recorded from Java. 



Pteroeides crassum, Kolliker. 

 Specimen. I. II. III. IV. V. VI. 



Total length of colony . 



Length of rachis 



Breadth of rachis 



Length of stalk . 



Thickness of stalk 



Number of pinnules 



Number of rays . 



Length of pro-rachidial mar- 

 gin of largest pinnule . 28 mm. 21 mm. 21 mm. 18 mm. 14 mm. 11 mm. 



Breadth of insertion of lar- 

 gest pinnule 



Breadth of largest pinnule 



Distance between pinnules 



Six specimens represent this species. The colour of the stalk and keel is 

 yellow, with green, blue and purple streaks ; that of the pinnules is pale yellow 

 while the polyps are brown with blue markings, the latter giving the character- 

 istic appearance to the colony. The rachis, when viewed from the meta- 

 rachidial surface, is heart-shaped, but from the pro-rachidial surface it appears 

 oval. The pinnules are broad and fan-shaped, but the lower rudimentary forms 

 are scalpel-shaped and approach the pro-rachidial surface. The number of rays 



