ACTINIAN BUNODEOPSIS GLOBULIFEEA. 299 



The tentacles are margiuate, strongly entacmteous, and very variable in number and 

 size. Any number from twelve to forty-eight may be present, according to the size of the 

 polyp. Verrill records examples with 18, 20, 22, 24, and 26 tentacles. Three or four 

 cycles are represented, but no regular an'angemcut, hexameral or otherwise, has been 

 made out. The inner members are mostly very long and slender, tapering towards the 

 extremity, and are smooth, very delicate, and transparent, and sometimes appear 

 minutely spotted. Very often the tentacles are imperfectly developed at some particular 

 region of the periphery, several appearing much shorter than the others, or represented 

 only by mere papillae. As a rule one such imperfect area will occur, but there may be 

 two, separated by one or more fully developed tentacles (PI. 25. fig. 1 b). 



The tentacles are generally overhanging in living polyps, and in preserved specimens 

 they remain nearly erect and tapering, and a little shortened. On one or two occasions 

 they have been found completely infolded, with nothing but the vesicular part of the 

 column showing. Though such a strongly infolded condition is rather exceptional in 

 the present species it is very frequent in B. autilliensis, Duerd., and is somewhat 

 remarkable considering the practical absence of a sphincter muscle on the column 

 (p. 302). So complete is the infolding that the tentacles may even pass into the 

 mesenterial chambers, as shown in fig. 11. A basal constriction often occurs at the origin 

 of the tentacle from the disc (fig. Ic), and occasionally a tentacle has become detached, 

 its former position at the margin of the disc being indicated by a circular aperture. 

 The tentacles are thickest just above the basal constriction. 



The disc is smooth, circular, flat or slightly convex, and transparent the mesenteries 

 and stomodteum showing through iu the living condition. The central part as a rule is 

 elevated in preserved polyps. The mouth is slit-like in living polyps, but in preserved 

 specimens it is widely open and circular, and tlie lips are thickened and j)rotruduig. 

 The stomodseal walls are smooth, and no gonidial grooves are distinguishable. 



The polypal wall thi'oughout is nearly transparent and only slightly coloured. 

 During partial contraction the lower part of the column is sometimes a bright, opaque, 

 yellowish green, with brown or black lines or spots. On fu^ll distention, the vesicles and 

 column are a clear, delicate, yello^vish brown, due to the yellow cells within the 

 endoderm. The tips of the larger vesicles may be a little darker than the rest of 

 the wall, probably owing to the greater concentration of the stinging-cells (fig. 5). 



The diameter of the base of the largest specimens is 12 cm. ; the height varies from 

 0'5 cm. to 1'3 cm. The length of the inner tentacles is about 1 cm., or nearly the same 

 as the height of the column. 



The polyps are essentially shallow-water forms, being usually met w'ith around 

 Jamaica at a depth of three or four feet, with their base encircling the long, narrow, 

 cylindrical stems of the marine weed Ruppia, or more rarely adherent to the flattened 

 fronds of Dictyota and leaves of Thcdassia. It occurs in some abundance at Port 

 Antonio, and I have also found it aroimd Kingston Harbour. In this latter area the 

 closely allied B. antilliensis is very abundant, but I have not met with it at the former 

 locality. 



44* 



