24 BULLETIN OF THE UNITED STATES FISH COMMISSION. 
It would be absurd to attempt to make any specific character dependent on such 
slight differences, but in the other calcareous particles in the body wall, roseola dif- 
fers markedly from inhcerens. In the skin of the tentacles, especially on their inner 
side, we find in inhcerens some small, simple particles, not at all branched (fig. 3). In 
roseola these particles are more numerous and are always very much branched and 
perforated (fig. 4). In the longitudinal muscles of inhcerens are numerous small, 
round, or sometimes dumb-bell shaped, particles; they are never branched or perfor- 
ated (fig. 5). In roseola the concretions of the longitudinal muscles are either 
C-shaped or perfect circles; more rarely they are somewhat branched (fig. 6). These 
differences, though seemingly slight, are remarkably obvious and constant and no 
signs of intergradations were found. 
(3) The third characteristic of roseola is found in the size and shape of special 
ciliated funnels. In both species these large ciliated funnels seemed to be confined 
chiefly to the mesentery of the left dorsal interradius and occur singly every milli- 
meter or two. Semon (’87) speaks of two sorts of ciliated funnels in digitata , but he 
does not seem to have observed them in inhcerens. In the latter species the large fun- 
nels are from 400// to 1,200// high, aud from 150// to 400// in diameter. Their shape is 
shown in fig. 7. In roseola they are smaller and much more slender, measuring less 
than 300// high and 80// in diameter (fig. 8). 
In addition to these points of anatomy, there are noticeable differences in habitat 
between the two species; inhcerens occurs in sand or sandy mud, or even in pure mud, 
less commonly along gravelly shores; roseola occurs on rocky or gravelly shores under 
stones or among the pebbles, and never in pure sand or mud. I have never found 
roseola except where there was sufficient iron present in the soil to give it a decidedly 
rusty color, and it has occurred to me that there might be some connection between 
the very unusual amount of pigment developed in roseola and this excess of iron. 
Some specimens of inhcerens show more or less pigment wheu carefully examined, and 
several specimens among those received from Naples were as rosy in color as the 
average roseola , but none of them show any approach to that species either in the 
calcareous ring, the concretions in the body wall, or the large ciliated funnels. Until 
intergradations are shown and some better explanation is offered of the constancy 
with which these characters separate roseola and inhcerens , it seems to me they must 
be regarded as distinct species. As Verrill’s description of roseola is so incomplete 
and is also erroneous, I venture to give the following summary of its characters: 
Synapta roseola (Ver. ). 
Leptosynapta roseola, Verrill. Rep. on the Inv. Ani. of Vineyard Sound, 1874, p. 422. 
Synapta roseola, (Ver.), Thdel. Report of the Challenyer, The Holothurians, vol. xiv, 1886, 
pt. xxxix, p. 25. 
More slender than inhcerens and general appearance much more soft and delicate; usually much 
smaller, rarely exceeding 100 mm. in length, even when extended. Body wall white or colorless, thin, 
hut thickly covered with verrucae, which contain numerous pigment granules of a reddish color, 
giving a generally bright rosy color to the animal. The pigment resembles that found in S. digitata 
(Mont.) (see Semon, ’87) in that it is scarcely at all bleached by alcohol even after mouths, but it is 
entirely destroyed by acids or corrosive sublimate. Rarely the body wall is yellowish or pale buff, 
making the general effect reddish-yellow. Tentacles 12, each with 2 or 3 (rarely 4) pairs of digits 
and with 7 to 15 sensory cups on the inner side. Genital glands much branched, and when filled with 
the sexual products very conspicuous through the pink skin. Polian vessel generally single. No 
cartilaginous ring. Calcareous ring narrow, the radial pieces not perforated for the passage of the 
nerves, but simply notched on the upper edge. Ciliated funnels numerous, of two kinds; the largest 
ones, measuring about 300// high by 60// in diameter, infrequent, confined almost exclusively to 
the left dorsal mesentery; the smaller ones measure hardly one-fourth as much in height but 
