136 H. BOSCHMA 



HouTTUYN. The data noted here contain the original contributions towards a know- 

 ledge of the species ; remarks in other eighteenth-century publications were copied 

 from the cited works. 



According to Pallas, the colonies of his Madrepora rosea •are " semi-palmares " 

 (half a hand high, about 5 cm); Esper records the height of large specimens as " zwey 

 bis drey Zollen " (about 5 to 1\ cm). The two authors further state that the basal 

 parts of the stems are comparatively thick, and that they gradually taper to very thin 

 terminal branchlets while giving off numerous side branchlets. At that time the only 

 known locality of occurrence of the species was " Mare circa Insulam St. Domingo " 

 (Pallas), " an den Kiisten der Insel Domingo " (Esper), the quoted passages referring 

 to the eighteenth-century name of the island Haiti in the West Indies. It stands to 

 reason that the corals which were collected nearly two hundred years ago came from 

 shallow water. 



It is interesting to note that the corals from Curasao, on account of their small 

 size and of their gradually tapering branches, closely correspond with the specimens 

 described and figured by Pallas, Houttuyn, and Esper, thereby differing from the 

 other species of Stylaster known to occur in the West Indian region, which attain a 

 larger size and have branches of a much slenderer growth. 



Lamarck (1816) placed the species Madrepora roseus in the genus Oculina ; Gray 

 (1831) erected the genus Stylaster, in which he placed the two species Oculina rosea 

 and O. flabeUiformis \ in 1850 Milne Edwards and Haime (1850-1854) selected 

 Stylaster roseus as the type of the genus Stylaster. In another paper (Milne Edwards 

 and Haime, 1850) there is a rather elaborate description of Stylaster roseus, in which 

 the authors state that they have never seen colonies of a larger size than a few centi- 

 metres, the thicker branches of which have a thickness at the base of 5 to 6 millimetres. 

 These data correspond with those of the corals from Curagao; in other details, 

 however, there are slight differences: Milne Edwards and Haime remark that the 

 number of dactylopores in the cyclosystems is from 10 to 14, most commonly 12, 

 while the diameter of the cyclosystems is nearly 1 mm, these figures being somewhat 

 higher than in the specimens from Curagao. The measurements of the ampullae in the 

 specimens of Milne Edwards and Haime (not over \ millimetre) perhaps indicate 

 that these were male ampullae. 



PouRTALES (1871, p. 83) remarks that Stylaster roseus is " abundant on the under 

 surface of blocks of coral rock, on the reef at Cruz del Padre, north coast of Cuba, 

 a couple of feet below low-water mark ". Moseley (1880, p. 79) refers to this occur- 

 rence of the species in almost the same words, and on another page {loc. cit., p. 77) 

 remarks that " ampullae are especially well developed in the shallow water Stylaster 

 roseus; those in the female stocks being very large and prominent ". 



A coral of rather common occurrence in depths of 120 to 324 fathoms (220 to 592 

 metres) off the Florida Reef was described by Pourtales (1868) as Stylaster erubescens; 

 with some slight changes this description again appeared in a later paper (Pourtales, 

 1871); the following details are taken from the latter, the terminology partly being 

 altered to a more modern wording: younger branchlets slender, with rather close-set 

 alternate cyclosystems, these slightly prominent, 1-2 to 1-5 mm in diameter, deep; 

 nine to twelve, most frequently eleven dactylopores in a cyclosystem; gastrostyle 

 deeply sunk, rounded and hirsute; dimensions, height and breadth of flabellum, 

 10 cm. On Plate 4 of the cited work is figured a colony of Stylaster erubescens in 



