SiMi'SON — A RciHsion of tlie Gor(joneUi(l(ie. 117 



disposed mainly in two longitudinal series; but deviations from this type 

 occur, owing in some cases to overcrowding, in others to the anastomosis. 

 The verrucae are usually low and dome-like. Tlie spicules consist of (1) small 

 double-clubs and elongated double-clubs, and ('!) lung duuble-spiudles and 

 simple-spindles. Tiiese two sets are quite distinct ; but the spindles are not 

 so disproportionate in length to the double-clubs as in most other species. 



Nicdla moniliforme. 

 Colony simple or feebly branched, slender, filiform, and of almost uniform 

 diameter throughout ; polyps disposed in two longitudinal series, near the 

 tip in one row, but in the older parts in two or more indefinite rows in each 

 series. The spicules are very characteristic. They include small (li,iiil)le- 

 clubs and elongated slender double-clubs : also spintlles of two kinds 

 (1) long, slender, ninny spindles, and (2) loiuj, thick, denseli/ warlcd spindles. 

 The spindles are sometimes more than twice as long as the typical double- 

 clubs. (See figs. 117 and 118.) 



XXXI 1. Nicella dichotoma Gray. Fig. 114. 



Scirpearia dichotoma Gray, xi., p. 481. 



Nicella mauritiana (Gray), xii., p. 40, fig. 12. non Media mauritiaiM 



Studer. 

 Nicella dichotoma Ridley, xxix., p. 130. 



Nicella dichotuma Thomson and llussell, xliii.,p. IGl, I'l. vii., tigs. 1 and 5. 

 Nicella laxa Whitelegge, xlix., p. 319, Tl. xvii., figs. 30-33. 



This species was established by Gray in 1859 under llie name of Scirpcarm 

 dichotoma. He defined it tlius : — " Coral fan-like, in a single plane, irregularly 

 dichotomous. Gells cylindrical, elongateil, truncated, in a row on each side 

 of the branches, sub-alternate." Z(3ca/%. —Mauritius. In 1870 ho formed 

 another species, Nicella mtmritiana, while he gave as a ^ywitwywx Scirpearia 

 dichotoma. Since this new species is the same as the older dichotoma, it was 

 unnecessary to give it a new name, although he referred it to a new genus, so 

 that the newer name must give way to the older. The description of Nicella 

 mam-itiana is as follows : — 



" Coral fan-like, dichotomously branched ; stem cylindrical, longitudinally 

 striated; bark thin, pale brown; cells elongate, cylindrical, longer than the 

 diameter of the stem, ascending, truncated at the tip, placed rather irre- 

 gularly, sub-alternate (rarely sub-opposite) on each side of the stem an.l 

 branches; axis pale greyish-brown." ZotW%.— Mauritius. 



Eidley in 1882 re-identilied the species, and dcscribeil some specimens 



