THE GEM PIMPLET. 191 



margin like serried teeth. In contraction the surface is thrown into trans- 

 verse wrinkles, which of course pass between, and not across, the warts, and 

 thu3 a latticed or decussate appearance is communicated ; — as if each wart 

 were the centre of a little square. 



Disk. Flat or slightly concave ; the outline circular and plane, a little 

 overlapping. Gonidial radii strongly developed. 



Tentacles. In four rows, containing 6, 6, 12, 24 = 48; corresponding to 

 the lines of warts. They are sub-marginal, thick, moderately long, conical, 

 obtuse ; decreasing in size from the first row outwards ; and are generally 

 carried arching over the margin, or bent into a double curve, like the 

 branches of a candlestick : often, however, they assume a clumsy, thickset 

 form, swollen in the middle (see fig. 3). 



Mouth. Raised on a blunt cone. Lip furrowed. Gonidial tubercles 

 prominent. 



Colour. 



Column. Rose-pink, varying in brilliance, and often becoming brownish 

 towards the summit. Primary warts white, making conspicuous longitu- 

 dinal bands, which in the button state form a beautiful radiating pattern. 

 Secondary and tertiary warts bluish- or reddish-grey, the former generally 

 paler. Quaternary warts generally indistinguishable from the ground 

 colour. Sometimes, however, the quaternary row which bounds each 

 primary on each side is also white (see fig. 3). 



Disk. Ground colour bluish-grey on the outer region, blending into a 

 fine yellow-green around the mouth : each radius is bounded by a scarlet 

 line, lost at about half-disk; the primary radii are often marked with 

 darker and paler portions, sometimes even black and white ; and the result 

 is a brilliant kaleidoscopic star, of varied hues, the blue and scarlet lines 

 in particular running out among the tentacles. 



Tentacles. Pellucid grey or whitish, the front face 

 olive, undefined, and deepening into black in the median 

 line, often with a purple reflection : this face is crossed 

 by about half-a-dozen large transversely-oval spots of 

 opaque white, occasionally interchanged with more nar- 

 row and even linear ones. These spots are well-defined, 

 and, though they vary in the tentacles of the same in- 

 dividuals, are never wanting. 



Mouth. Lip whitish : gonidial tubercles grey, each ' li 



marked with a central dot of bright rose-colour. tentacle 



{lateral view). 



Sizb. 



Rarely exceeding an inch in diameter, and an inch and a half or two 

 inches in height. 



