6G RKCKNT MADKKI'OUAUIA OF THK HAWAIIAN ISLANDS AND LAYSAN. 



ritltfos iiiid tiiK' loriuiiudiiwil striatioiis, while Iroiu place to place there are more or 

 less eontimious. shar[)ly iiidented, loiii^itudiiial siilcatioiis. 



The septa do not show any deliiiite cyclical arraiij^'-enient. In one-half of the 

 next to the hist calice (diameter 1S.5 mm.) there are 17 septa which are, with one 

 exception, alternately larocr and smaller. The laryest calice has 36 septa, alter- 

 nately larger and smaller. Nineteen of the septa extend to the columellar space, 

 while ten have i)alifrom lobes on their innei' ends. Between ahuost every pair of 

 the 36 septa is a wide, low, rounded ri(l<;e, probably a rudimentary septum. Neglect- 

 ing- the ridges in tlie interseptal ioculi, the septa are distant, their outer ends are 

 thick, but they become thinner toward the columella. V\)\)ev margins strongly 

 arched, tiie arch not extending to the wall, the septa set within the epitheca which 

 extends upward beyond their outer ends. Inner margins of the larger septa steep, 

 the smaller septa becoming narrow toward th(^ ))ase of the corallum. Septal faces 

 irregularly and minutely gi-aindated. 



Columella false, poorly developed, formed of the loose fusion of the paliform 

 lobes and of a few septa that do not bear lobes. 



Calice moderately deep. 



Locality. — Stiition 3',»!>1, vicinity (^f Kauai Island; depth, 272-296 fathoms; 

 bottom, fine sand rock; temperature of bottom, 43.7- F. 



7////<'.— Cat. No. 20731, U.S.N.M. 



Ri-taarJi's. — This coral presents so little resemblance to an}' other one known to me 

 that scarcely any comparison can be made. From its general appearance it evidently 

 should l)e |)lace(l near Flahcll uin and Rhizotrdchiin. 



Genus PLACOTROCHUS Milne Edwards and Haime. 



PLACOTROCHUS FUSCUS, new species. 

 Plate IV, tigs. 2, 2((, :^, ■Mi. 



This species is represented by three specimens, all of which were used in preparing 

 the following description. 



Corallum small, trum])et-shaped. attached by an expanded l)ase. 



MEASUREMENTS. 



Specimens Nos. 1 and :'. have been broken from their Imses, and the measurements 

 given in the tal>le therefore do not represent the totAl height of the coralla. 



