102 KKCKNT MADKKI'OHAUIA i"!' TlIK IIAWAriAN ISLANDS AND LAYSAN. 



iiiiirtiiiis ail' oxsiMt. often decidedly prominent, sometimes as much as 2 mm. Sec- 

 ondaries thinner than the piiniaries: teiliaiies sliorter and thinner than the second- 

 aries, their inner edges usually l'n>e, hut some! lines fused to the sides of the secondaries. 

 Septal mar-rins denticidate. deiUieulalions (•t)arser near the cohimella. Septal faces 

 denselv <iranulate. Hndotiieeai dissepiments ])resent. scanty; exotheca solid. 



Columella false, formed of trahecuhe inclined inwardly from the inner ends of 

 the sepia. 



Asexual reproduction lis huddinu' <in llie intercoi-allite areas. 



Localitie.'i. — Kiwu'nkr. Oahu. I specimen: Waikiki. Oahu; depth. 3 to 6 feet; 

 received from W. T. Bri<iliam. 



Cofyjx'i.—CiiU Nos. 21t;;;:!. iMtKU. r.S.N.M. (5 specimens). 



Remarks. — One of the specimens of this species is interesting because of the way 

 in which portions of it have inerusted some small Serpula tubes. The specimen 

 looks as if it were ramose, one projection having a height of about 13 mm. and a 

 basal diameter of -1 mm. In the center of the piece is a worm tube less than 0.5 mm. 

 in diaiueter. There is a considerable nuiuber of these projections, of varying height 

 and thickn(>ss, and a worm tul)e can be seen in each one. 



The United States National Museum has obtaiiu>d one additional specimen of this 

 species, also from Kaneoke, from the Duerden collection of Hawaiian corals. 



Critical notes on L. agassizi and L. hctwat'iensin will follow the description of 

 the latter species. 



LEPTASTREA HAWAIIENSIS, new species. 

 Plate X.XV, lifjs. I, \,i. 



The corallum grows as a thin incrustation over ol)jects, its upper surface show- 

 ing irregularities corres[)onding to those of its basal support. 



The corallites possess free upper portions, which decrease in size from their 

 bases to the calicular margins and project from 1 to 1..^ mm. above the intercorallite 

 areas. The free portions are extei-nally beset with low, eijual, granulate, flattish 

 costa' that becoiue smaller toward the bases and on the intercorallite areas. 



The calices are moderately deep, circidai' or subcircular in cross section. They 

 are about 2 mm. in diameter and are separated by intervals of 1 to 2 nun. 



The septa form tliice complete cycles. They ar(> all of approximately the same 

 thickness iti the thecal i-ing. but their margins vary in proiuinence according to the 

 cycles. The primaries are moderately exsert. and all of them extend to the colu- 

 mella. Near the wall they are considerably thickened, but becoiue suddenly thinner 

 near the columella. The secondaries liav(> less exsert margins and are thinner than 

 the primaries, but two of them, those in the median lateral systems, usually, and 

 others occasionally, extend to the columella. The tertiaries have slightly exsert 

 margiii.s. They are thin and short and have fre(> inner margins. The margins of all 

 the sej)ta are finely denticulate; ])alifoi'm lobes often occur on the larger septa. The 

 septal faces are finely graiudafe, with some perforations near the columella. A few 

 endothecal dissepiments present; exotheca dense. 



The columella is spongy, false, composed of lobes from the inner ends of the 

 principal sepUi. 



