MADEEPORAEIAlSr SUBFAMILY LOPHOSEEIK^. 311 



are equal, the columella but little dev eloped, and the series are 

 short and the valleys deep- 



A species from Mergui, which resembles P. speciosa, so far as 

 Dana's illustration is concerned *, and were it not for the equality 

 of its septa would come fairly under that name, has been exa- 

 mined. 



The structural details of the coral are remarkable ; and I have 

 never had an opportunity of examining a specimen of Dana's 

 type. Hence I call the form under consideration PacTiyseris spe- 

 ciosa provisionally, my object being to bring forward the internal 

 structure rather than to deal with specific attributes and compa- 

 risons in this instance. 



The form is in thin leaf-like shapes fixed where narrowest, and 

 expanding on one plane, or becoming twisted up and curved. The 

 inferior or basal surface is marked with slender costge alternately 

 large and small, the larger projecting slightly ; they correspond 

 with septa at the edge of the corallum which are equal in breadth. 

 The surface is minutely granulo-spinate. 



The series are very long, irregularly concentric, and bifur- 

 cating here and there. The coUines are moderately deep and 

 slightly inclined. The septa are very numerous, close, equal, 

 thin, finely dentate where free, sometimes wavy and bent, and very 

 granular on their sides. The columella, seen from above, fills 

 the axial space, and unites the opposite septa in a continuous 

 gutter. 



An exaaiination of the structures shows that whilst the lateral 

 granulations of the septa are profuse, and occupy much of the 

 interseptal loculi, the synapticulse are usually noh seen from 

 above. These are suflSciently distant from the free edges of 

 the septa not to be visible ; but near the edge of the corallum, 

 where growth has gone on lately, the bodies can be seen, and 

 are clearly not united or fused ornamental granules. 



A section through the corallum shows the thin and very solid 

 basal lamina from which spring the septa. These are slender close 

 to the base, equ.al and with well-defined interseptal loculi. The 

 lowest synapticula are nearly everywhere at the samelevel at a little 

 distance above the basal lamina. Above the first row of synap- 

 ticula the septa are broader, and, in section, their outline is very 

 irregular on account of a succession of small ornamental granules 

 and large synapticula and of synapticula not sufficiently developed 

 * Dana, ' Zoophytes, Explor. Exped.' pi. 21. fig. 7. 



