THE ECHINODEEMS OF PORTO RICO. 
257 
1. Eehinocucumis asperrima The61. (PL 16, figs. 1-7.) 
This extraordinary holothurian is 1 or 2 inches long, including the long neck and slender, tapering 
tail. It has been recorded from only the Caribbean Sea, and there only in deep water. 
There is one specimen of this species dredged at station 6066, in 170 fathoms of water. It is just 
24 mm. long, and the delicacy and glassiness of its appearance make it an object of unusual interest. 
The species was first described by Theel, in 1886, from specimens collected in the vicinity of Jamaica 
and Cuba, at depths of 150 fathoms or over. As he published no figures of the species, it seems worth 
while to give with this report some illustrations of such a noteworthy form. The tentacles (fig. 4) 
are apparently only eight in number, and differ from the tentacles of all other pedate holothurians in 
being perfectly simple, without branches of any kind. The calcareous ring (fig. 2) is very small; no 
stone canal or Polian vessel found. Genital filaments few, but thick. Respiratory trees very delicate. 
No Cuvier’s organs. Respiratory trees and intestine with numerous brownish spherical bodies in 
their walls, possibly waste matter. Intestine very long and much coiled. Pedicels very scarce, almost 
wanting, except near head and tail. Body-wall (fig. 3) very hard and firm, as though mailed, pure 
white. It is composed of more or less regular polygonal plates, each of which bears a single, long, 
stout and sharp spine. Calcareous bodies (figs. 6 and 7) consisting of irregular plates with numerous 
holes, very abundant, especially in and near the tentacles. 
2. Stichopus moebii Semper. 
A common species and very interesting on account of the great variety in the color, shape, 
appearance, and number of tentacles. It reaches a length of 300 mm. or so. The body-wall contains 
numerous tables and C-shaped bodies; the former with well-developed disk and numerous teeth at 
top. Known from Bermuda and the West Indies. There are 8 specimens of Stichopus in the Fish Hawk 
collection, varying in size from 90 to 220 mm. Though differing somewhat in color, they all show the 
light background with large dark spots and blotches. The number of tentacles varies from 16 to 20, 
there being 1 with 16, 1 with 17, 2 with 18, 1 with 19, and 3 with 20. It is worthy of note that the 
two largest specimens have 20 tentacles and the two smallest have 18 and 16, respectively. This 
species was collected at Boqueron Bay, San Juan, and Mayaguez, and these specimens agree in all 
essentials with those from Jamaica and Bermuda. 
3. Holothuria captiva Ludwig. 
This little holothurian rarely reaches a length of 100 mm. It is rich brown in color, somewhat 
paler below. On the back are rather numerous papillae. The body-wall contains numerous tables, 
with many teeth at the apex, and buttons with 3 pairs of holes. The species is known only from Ber- 
muda and the West Indies. There are only two specimens from Porto Rico, and both are very small, 
12 and 15 mm. in length. They were collected at Hucares. The skin is very delicate, almost without 
pigment, but the deposits are numerous, full size, and perfectly formed. Color in alcohol dirty-brown. 
Cuvier’s organs very noticeable; in one specimen their bulk is fully one-tenth of the whole animal. 
The arrangement of pedicels, papillae, and tentacles is of interest. 
Specimens. 
Pedicels. 
Papillae. 
Tentacles. 
Smaller specimen 
15 in a row; a single row on 
each side, a double row in 
middle of ventral surface. 
Six longitudinal rows with 
10 
♦ 
6 papillae in a row. 
Larger specimen 
18 in a row; rows as above 
Six rows with 10 in a row . . 
14 
4. Holothuria densipedes, nov. sp. (PI. 17, fig. 1.) 
There is a single specimen, from the light-house reef at Playa de Ponce, of a holothurian unlike 
any yet described. On account of the very numerous and crowded pedicels, I have given to it the 
name densipedes. It is 88 mm. long and about 20 mm. in diameter. The color is brown, with a few 
scattered dull purple or blackish blotches. The papillae have a reddish tinge, while the pedicels are 
much lighter, with a touch of yellow. The pedicels are crowded on the ventral surface, and are 
2d— F, C. B. 1900—17 
