124 Natural History Bulletin. 



dividing pinnately. The entire zoophyte may be as much as 

 three feet in height and contain hundreds of branches. The 

 pinnate method of branching is sometimes obscured or inter- 

 rupted by single branches arising on the stem between the 

 bases of opposite pinnae and growing at right angles to the 

 plane of the latter. 



Color of zoanthodeme, a dark dull red, the polyp being 

 brown. Spicules show through from the surface. 



The individual branches are round, slender, and often 

 swollen slightly toward the ends, calicles forming small warty 

 prominences of slight elevation. They seem to be rather 

 evenly distributed on the branches called pinnae, and less 

 densely on the main branches. 



The entire zoanthodeme is extremely flexible and waves 

 gracefully with the slightest disturbance of the water. 



Polyps completely retractile, small and decidedly "thick 

 set " or " squat " in appearance when contrasted with those 

 previously described. When expanded, the body has its 

 greatest diameter a short distance above the surface of the 

 zoanthodeme. From this point there is a gentle curve of the 

 profile toward the center as it ascends, until the least diameter 

 is reached just below the bases of the tentacles. 



One of the most conspicuous external features of the ex- 

 panded polyp is the great prominence of the longitudinal 

 ridges and intervening depressions corresponding to the mes- 

 enteries and intermesenterial chambers within the body. In 

 some cases the spicules immediately beneath the ectoderm of 

 the zoanthodeme, are seen to invade the polyp walls them- 

 selves. 



The tentacles resemble in general contour those of Plexau- 

 rella dichotoma^ but are of course absolutely much smaller 

 (see fig. 3, PI. III). The mouth seems large in proportion to 

 the size of the polyp and is much elongated, a character show- 

 ing a tendency toward bilateral symmetry. 



The gullet \?, v^vy short and has few convolutions. It is 

 almost entirely hidden by the tentacles when the polyp is 



