No:-t] ACTINIARIA OF THE BAHAMAS. 35 
absent on one surface. The endodermal musculature is evidently 
a continuation upwards of that of the column wall, but it soon 
disappears, and a very short distance above the base the tenta- 
cles throughout their whole circumference resemble the disc. 
The pseudo-tentacles are six in number, and not five, as Du- 
chassaing and Michelotti (60) describe, one having evidently 
been overlooked by them, or else they chanced upon an abnor- 
mal specimen. In both of the specimens obtained at New Provi- 
dence six were present, and there can be no doubt but that this 
is the normal number. They alternate with the six primary 
tentacles. Each has a somewhat elongated stout basal portion, 
which measures 3.8 cm. in length by 0.8 cm. in diameter. This 
divides into two equal stems (Pl. III., Fig. 11), which again 
dichotomize many times until a dendritic structure is produced, 
which projects some distance beyond the decurved tentacles. 
In structure the pseudo-tentacles are somewhat peculiar. Trans- 
verse sections through the basal portion (Pl. III., Fig. 12) show 
the ectoderm to be identical in composition with that of the 
column, and the ectodermal surface of the mesogloea is raised 
into fine processes as in the column-wall. The musculature of 
the endoderm is, however, very characteristic, bands of muscle 
cells (wz) being arranged at intervals around the circumference, 
the surface in the portions intervening between the bands being 
destitute of muscle cells. A nervous layer can be traced all 
the way round, but is only well developed over the bands, being 
in the intervals exceedingly delicate and sometimes scarcely 
discernible. In the finer branches this arrangement of the 
endodermal muscles becomes much less distinct, and finally dis- 
appears altogether. In the terminal branches the ectoderm is 
markedly changed in structure, becoming densely loaded with 
nematocysts, while elsewhere, as in the column, these are absent. 
It may be remarked here that this is the only anemone of all 
those I examined and handled which stung at all severely, though 
this may in part be due to the pseudo-tentacles having come in 
contact with the more delicate skin between the fingers. Prob- 
ably in the same circumstances the stinging powers of Dzsco- 
soma would have been quite as marked. 
I was unable to ascertain the number of the mesenteries, but 
they are quite numerous, a pair probably corresponding to each 
tentacle. Half of the pairs are decidedly larger than the others, 
