BULLETIN 59, UNITED STATES NATIONAL MUSEUM. 215 



first two calicinal tenters, connected by septa extending from one to the other, are 

 formed in the series. These two centers heconic separated by a wall, synapticular 

 in character, developed between the connect iiij>f septa. Tlie division of the elon- 

 gate calice. it appears, can be brought about in either of these ways. However, 

 it may be that both methods act together, in most instances one being more pro- 

 nounced than the other. The walls bounding the series become considei-ably elc\atc(i 

 and thickened l)y reticular tissue. Winn walls develo)) between the calicinal cen- 

 ters in the sei'ies, they are, at first at l<'a>t, thin and not very ])rominent. In other 

 [jlaces the calices do not show any tendency to the arrangement in valleys, but are 

 uniformly distributed. In most instances the walls are thin and continuous. Tiie 

 frecjuency of perforations is variable. Sometimes mural pores are rare; in othci- 

 instances perforations are frequent, the walls clearly l)eing a vertical ring of synap- 

 ticula joining of the peripheral ends of the septa. The w:ill-< are often secondarily 

 thickened by reticular tissue. 



The arrangement of the septa is shown in tlie enlarged view of the calices. The 

 usual iuiinl)er of pali is live, four princiiKils. and one on the ventral directive septum to 

 which tiie lateral septa of the triplet fuse. The dorsal directive xcry i-arely bears a 

 palus. The pali themselves are slender, tali, rcadiing aliiiii>t the level of the upper 

 edge of the wall, and miiuitely grantdated. Betw(>en the ])alus and the wall a single 

 tooth can be seen on many se))ta: tliis tooth i)rolial)ly is < onstantiy ])re>('nt. Wher- 

 ever the upper edge of the wall is intact, ev en w hen tliickcned and icticular. there 

 is a dentation or spine on it coriespondiMg to tiie distal entl of each septum. The. 

 septa usually are thickened at the wall and there is more or less tiii<'kening in the 

 region of the columella, but a synajiticuiar ruig surrounding the columella is not 

 constantly present. S(>ptal fusion further than has been noted i> not regular. 



Usually the columella tci'mination is stylil'orm, the style prominent and slender; 

 in a considerable number of calice.s there is no style, but it may have been broken otf. 

 The columella is reinforced by the irregular fusion and thickening of the inner ends 

 of th<i septa. 



Locality. — Fiji Islands, United States Exploring Expedition. 



7)//'^/.— Cat. No. COe, r.S.N.M. 



Quelch, in his Challenger Keef Corals, p. ISl, cites this species from the Hawaiian 

 Islands, reefs at Honolulu. If one may judge by his notes he never seized .some of 

 the essential characters of the species, the wall in places forming the prominent, 

 thin lidges of Dana. The pali are not '"small and often scarcely appai(>nt," but 

 as they have just been described. Quelch's specimen-; are young, and belong in the 

 P. lohata series. 



i6. PORITES RETICULOSA Dana. 

 Plate Xr, ti«. ■'•■■ I'late XCI, lifp<. 1, l<i. 

 1846. Porites reliculosa Dana, Zoopli. Wilkes K\]>\. Kxix><l., p. iili'. pi. i.vi, (ig. .3. 

 Original dencriplinn. — Dana's original desci'iption is as follows: 



Incrusting, undulate, margin scarcely at all free, surfact? inarniiiillate ami tuberose. Corallum 

 very porous, cells neatly angular, shallow, rather large (three-fourth.<i of a line), plane at hottoni, 

 septa thin and often in thin ridges, like the lichen. 



