126 A. jEJ. Vevrill — BernmcUan and West Indian Reef Corals. 



Septa rather narrow and thin, closely arranged, their edges covered 

 with numerous rather slender, acute, rough teeth, the proximal ones 

 usually the larger. The sides of the septa and teeth are covered 

 with numerous, sharp, rough, conical grains, giving them a rough or 

 hispid appearance, under a lens. The columella is well developed, 

 rough, poi'ous, composed of small, irregular, contorted and hispid 

 lamellfe and spinous processes of the septa. There are usually 11 or 

 12 well-formed septa to a centimeter, besides some rudimentary ones. 

 The costae are not much elevated, except close to the edge, slightly 

 thickened, hispid laterally, and sharply serrate with small rough 

 spinules. The epitheca is imperfect, but usually covers much of 

 the lower side. 



The animals of this coral are smaller than in the other species, and 

 they form elegant crowded groups, when expanded. The colors are 

 similar to those of dipsacea and fragilis, but emerald-green is per- 

 haps a more common color in this. 



Our largest Bermudian specimen (pi. xx, fig. 1) is 40™™ thick and 

 85™™ across, with a nearly flat upper surface. This has 27 distinct 

 calicinal centers, of which only five or six are isolated, most of the 

 others forming series of two or three. The margin has about twelve 

 small lobes. 



A very regular small specimen (pi. xxi, fig. 1) is about 55™™ 

 broad and 25™™ high, with twelve small marginal lobes and twelve 

 radial collines, six of which are primary and extend to the central 

 calicle in sinuous lines, mostly uniting to the five-lobed colline sur- 

 rounding the central calicle, while the short secondary collines are 

 nearly radial and unequally developed. Each of the six primary 

 marginal calicles has already divided into three, more or less sepa- 

 rated calicles, and the secondary central calicle has formed four 

 smaller ones around itself, so that it is 5-lobed. Thus there are now 

 23 distinct calicinal centers on this small specimen. No. 4009. 



A considerably larger one of I. dipsacea or I. fragilis would 

 usually have but seven calicles. This rapid increase in the calicles 

 seems to be characteristic of this species, which often resembles an 

 astrsean coral, such as Acanthastrma, in the size and shape of its 

 calicles and septal teeth, though many of the calicles are not isolated, 

 like those of the latter. 



I am unable to refer this rather rare species to any of those 

 described by Duch. and Mich., or others,* unless it be the form 



* The Isophyllia Danaana (Edw. and H., as Mycetophyllia, Hist., ii, p. 377, 

 pi. D4, fig. 2) resembles this species in the width of the calicles and valleys, and 

 in its septa, but the valleys are long and sinuous ; the collines low and obtuse ; 

 and the columella is feebly developed. 



