POLYPS AND COEALS. 85 



porous and spongy, not papillose, and covered with more 

 distinct and larger cells (about .03 inch), which are sur- 

 rounded by a thickened, roughly spinulose and porous 

 border, somewhat elevated above the general surface. 

 They are numerous but irregularly scattered, and have 

 twelve distinct septa, six of which are larger. 

 Gaspar Straits. 



MONTIPORA FOLIOSA Edw. and Haime. 



Madrepora foliosa Pallas, 1766 (non Ellis and Solander, 1786, nee 

 Esper, Tab. LVIII B, tig. 1, 2, 1797). 



Porites rusacea Lamarck, 1816 (non Lamouroux, Plate 52). 



Montipora foliosa Edw. and Haime, Corall., Vol. 3, p. 212 (non Porites 

 foliosa Ehr., nee Manopora foliosa Dana). 



A specimen of this species, in the Museum of Yale 

 College, consists of a large cluster of very broad, thin, 

 convolute, unequal fronds, which are arranged somewhat 

 like the petals of a half-blown rose, but are somewhat 

 irregular in form and position. There are three fronds 

 between the centre and the outside on nearly all parts. 

 The spaces between the fronds at the summit, vary from 

 2 to 3.5 inches. Some of the fronds are 20 inches 

 broad, and over 12 wide. The entire height of the coral 

 is 14 inches ; diameter 18. The fronds are thin through- 

 out, scarcely exceeding .25 of an inch in any part, and 

 usually about .12 at one or two inches from the margin, 

 which is much thinner and translucent. Texture very 

 porous, rather fragile. On the outside the surface for an 

 inch or more from the margin is nearly destitute of cells 

 and not papillose, but crossed by irregular and very 

 unequal, distant, vertical ridges. Below this the cells 

 gradually become more numerous and crowded, and the 

 surface more uneven. The cells are between .02 and .03 

 of an inch in diameter, slightly elevated, and surrounded 

 by small, rounded, rough papillae, and with similar minute 

 papillae between. Septa small, six distinct. On the inner 

 surface the cells are of about the same size, but are sur- 

 rounded by much higher, very slender, rough papillae, 

 while similar but shorter papillae are thickly crowded 

 over the whole surface between the cells. Towards the 



