BULLETIN 59, UNITED STATES NATIONAL MUSEUM. 159 



.SYNOPSIS OP TIIK HAWAIIAN SPEOIIiS OF MOXTIPOUA. 



1. (ilahro-foveolate: 



Coralliim a horizontally cxpaiuU'il. thin, laterally attached lamina 1. ^f. diUildtn. 



II. Papillate: 



Papilhi' nipple-shaped. 



Corallmn, ])reseritinf; a variety of growth forin.s 2. M. verriwom. 



I'apilla' as hoods helow the calices. 

 Coralluin ramose. 



Branches slender, papillie not proniiiieiit 3. M. tenuicnulis. 



Branches thicker, papilhi prominent 4. ^f. hemardi. 



Coralhim laminate or foliaceous. 



Under surface with little epitheca, calices ciccurring at the base of the outward steep 



slope of the papilUe a. M. fiabdluta. 



Under surface entirely covered with epitheca, calices frequently occurring on the 



outer end or upon the papilhe 6. M. xluderi. 



III. Tuberculate: 



Coralhim with wide, free edge, calices sunken 7. M. palala. 



CoralhiMi with a narrow or no free edge, calices frecjuently elevated 8. il. verrilli. 



I. GLABRO-FOVEOLATE. 



I. MONTIPORA DILATATA Studer. 



I'latc l.II, fit:. 1; Plate XCII. 



1901. Montipora dilatata Studkr, Zool. Jahrb., Syst., XIV, p. 419, pi. xxx, fig. 11. 



Deitci'iption. — The original de.scription is a.s follow.s: 



The coral builds a horizontally exiianded thin lamina, which is attached laterally. The under 

 side is covered by an epithecal coating, which leaves a thickened free edge not measuring more tlian 

 10 mm. across; the calices are very small, 0.5 mm. in diameter, and are sunk in the reticulate ctenen- 

 chyma. On the upper side the calices are 0.8 to 1 mm. in diameter, more or less crowded, separated 

 by a reticulate co^nenchyma, beset with fine, branched spinules, which stand close around the calices, 

 so that in some instances the calices appear surrounded by a wall. The calices often contain a second 

 incomplete cycle. 



Studer possessed two specimens of this species and added the foilo\vini>- notes on 

 them : 



One colony is a flat, expanded, fan-.<haped lamina, whose inner attached portion is dead and cov- 

 ered by a white coat; the living part shows on the ujiper surface concentric, wave-like elevations and 

 depressions, the first ones of these again show irregular elevations, on which, when the calices are 

 closely crowded together, the ca'nenchyma is more pushed up and surrounds the calices with a pro- 

 jecting wall. The lamina is 3 mm. thick on the edge; toward the base, 4 nun. 



A second colony, a laterally attached lamina, 45 mm. across from the edge to the place of attach- 

 ment and 125 mm. in breadth, is dead, but a great portion of it (in three places) has subsequently 

 been covered by a new living layer, which extends over half of the old lamina and projects beyond 

 its edge. The old dead colony has Sirpida tubes growing through it and projei'ting above its surface. 

 These have been overgrown by the new layer, which is consequently thrown into numerous rounded 

 protuberances that may be as much as 10 mm. tall. The calices on these are l)rought nearer together 

 through the changed mode of growth, and the cienenchyma between them pushes upward, or the 

 calicular mouths are elevated, the calices rising above the general level of the surface. In a third and 

 similar case, where the lamina appears much folded, the protuberances caused by the Serpiila tubes of 

 the substratum or by an attached cirrepede (Pipyoma) are cylindrical or club shapetl, and may be 16 

 mm. tall. Here the calices are closely crowded, and the intervening civnenchyma rises like a wall 

 above the cali<ular mouths, producing what may lie calleil foveolate structure, using the language of 

 Bernard . 



