290 



The zooid-plate is large and basal, extending almost to the polyp region. 

 The meta-rachidial zooid-streak is long and narrow, consisting of a single row of 

 widely separated zooids towards the npper extremity. The rays, which are 

 about twenty-five in number, are not very prominent and in only a few cases 

 project beyond the margin. They are only faintly visible to the naked eye. 

 The polyps are numerous, the greater number being congregated along the 

 margin, but a few occur on both surfaces, though mostly on the upper side. 

 The keel is very broad and is bare on both the pro-rachidial and the meta-rachidial 

 aspects. The colour of the colony is orange-yellow. 



Locality : Unknown ; No. MjL* Marine Survey. 



Previously recorded from Pulo Penang (Expedition of the " Galathea " ). 



Pteroeides intermedium, n. sp. Plate VI. fig. 9. 



esents this species. 



75 mm. 



45 mm. 



40 mm. 



35 mm. 



7 mm. 

 18 



8-10 

 19 mm. 



45 mm. 

 16 mm. 



2 mm. 



A single colony very much expanded in one plane repr 

 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 margin of largest pinnule 

 Breadth of insertion of largest pinnule . 

 Breadth of largest pinnule .... 

 Distance between pinnules .... 



This specimen has a basal zooid-plate and the rachis is slightly longer than 

 broad, so that it is included in Kolliker's lacazii-group. The number of rays is 

 about eight to ten, and thus it is intermediate between P. kartimjii, Kolliker, 

 and P. lacazii, Kolliker, the former having four to six and the latter eleven to 

 sixteen rays. 



The keel and stalk are moderately soft, and both the meta-rachidial and 

 pro-rachidial surfaces are free throughout their entire length. The pinnules are 

 almost scalpel-shaped and have a very narrow insertion. All are distinctly 

 lateral, but the rudimentary forms at the base turn towards the pro-rachidial 

 surface. The pinnules are thin and flexible and bear a few small limy needles 

 in the polyp-zone. There are also minute spicules in the keel and stalk. The 

 rays consist of six or eight spines and are very strong. They project markedly, 

 sometimes extending 4 mm. beyond the margin. On the lower surface they 

 are very prominent, but on the upper surface can be discerned only with difficulty 



