inO KKCKXT MADREPORARIA OF TIIK HAWAIIAN ISLANDS AND LAY8AN. 



P. 7neandri>i(i is extnnncly close to P. verrucosa; in talicular characters they 

 overhip. TIio verruca" of the hitter arc larger and more irregular in size, causing 

 the coi'alluiu to have a very rough, even a ragged appearance. P. damicm-nis, 

 dame, verriicoM, meandrina, and fJe(jaM form a series so indistinotl.y brok(>n tliat one 

 is led to suspect that they are ri^ally continuous. It is probable that /'. hx'rirornis 

 and P. Ii>l)lf(-rii arc a part of the same series. 



P. riieandrina, typical or as tlie form called nohills, is widely distributed. The 

 Alhn/roKs south Pacific exi)(>dition of 1899-1900 obtained 1.5 specimens and a frag- 

 ments that I hav(> lal)eled /*. ineandrina. They were obtained from the following 

 localities: Reef. Lagoon, Makemo, Fauniotus, S specimens; Reef, Lagoon, Apataki, 

 I'aumotus, 2 specimens: Reef. Funafuti, Ellice Islands, 2 specimens; Papeeti Harbor, 

 Tahiti. 1 specimen; Rangiroa. 2 specimiMis. and locality la))e]s lost, 2 specimens. 



The general cliaracter and range in variation of these specimens are so similar 

 to those from the Hawaiian Islands tliat no notes of importance can be made. 



7. POCILLOPORA INFORMIS Dana. 



Plat.- XXIV, li-s. 1, \a. 



1S4I). Pocillojiora injoriiilx Dana, Zciopli. Wilke.'^ Kxpl. Expeil., p. 535, pi. 1,1, figs. 3, 3a. 

 1860. Pocillopora informls Mii.nk I'j)\VAiti>s, Hist. Nat. Coral). , III, p. .'OT7. 



Ori<jinid (hxcri/itinn. — Dana dcscribi's this species as follows: 



Glomerate-cespitdse, soliil at base, braiichiii}; ii'regiilar, often gibbous and aeervate, in part naked, 

 in part remotely anil irregularly verrucose. Coralluui having the cells small (J of a line), a slender 

 columella, and one lamella very <listinct. 



Forms rough-looking clumps, often a foot through, which are massive at base, and very irregu- 

 larly subdiviiled above. The surface is often bare of verrucie in many parts, and in others is very 

 uneven, and gives off rudimentary l)ranchlets or jirotuberances _of various shapes. 



Ti/pe. — Cat. No. tt-H, U.S.N. M.. frnnithe "Sandwich Islands," Wilkes Exploring 

 Expedition. 



Dana's description, so far as it goes, is excellent, and gives the most striking 

 characteristics of the specie^. His figures also are good. It is desirable, however, 

 to have certain features described in greater detiiil. The calices vary in diameter 

 from 0.6 to 0.9 nun.: lliey are deep, 1.3 to 2 nun.; separated by narrow walls, rarely 

 exceeding <>.() mm. across and usually less. The septa, excepting one, are u.sually 

 rudimentai-y or ol)solete, but are sometimes distiiu^t, when they are small and narrow. 

 Columella tall, styliform, attached to an elongated septum. 



Tiie cuMienchyina between the calices is .solid, its surface densely granulate, the 

 granulations ratiicr coar.-^e. The corallite cavities may or may not be filled with 

 internal dejwsit. sometimes there is a succession of tabuhv to the bottoms of the 

 calices. again a corallite cavity is solidly filled for a .space and then the succession of 

 tabuhe is resumed. It is interesting to note in longitudinal sections that the principal 

 septum (to which the colmnella is attached) may be continuous across .several tabuhe, 

 then it may be alxsent across .several, and appear again. 



This species is so very distinct that extensive critical remarks on its athnities are 

 not necessary. Its growth form immediately separates it from the other Hawaiian 

 Pocillojwnv. Its styloid columella and ol)soiescent septa are additional characters. 



