BULLETIN OF THE UNITED STATES FISH COMMISSION. 
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numerous, though somewhat smaller, dorsally. The papillae are numerous and confined to the dorsal 
surface. There is no sign of arrangement in rows of either the qiedicels or papillae. Tentacles very 
small and pale, apparen tly 20. Polian vessel 1 . Stone canal 1. Water-ring with many small bead-like 
bodies on it. Cuvier’s organs present; small, greenish. Genital glands with numerous infrequently 
branched filaments. The calcareous deposits consist of tables and smooth buttons, with numerous 
supporting rods in pedicels, papillae, and tentacles. The buttons usually have three pairs of holes, 
but not infrequently there are only 3 or 4 holes. The tables have the disk with 4 large central 
holes or a single deeply 7-lobed hole, surrounded by a circle of smaller holes, 4 larger alternating with 
4 smaller, to complete the circle. The spire is comparatively low, with only 1 crossbeam and few (not 
more loan 10 or 12) teeth. The tables of the pedicels are usually much reduced. 
The supporting rods of the tentacles are simple, slightly rough or knobbed at ends. Those from 
the pedicels are usually broader and pierced by holes more or less symmetrically arranged. There are 
often 7 or 8 pairs of these holes. The calcareous ring is composed of 5 large radial pieces and 5 small, 
narrow, pointed interradial plates. The calcareous ring and the various calcareous deposits are 
exactly like those of H. rathbuni Lampert, from which species this form is otherwise radically different. 
(See pi. 17.) It differs from its nearest allies in the crowded papillae on the dorsal surface, as well as 
in the detailed structure of the tables, while it differs markedly from If. glaberrima in the large size of 
the pedicels and papillae, and in their crowded arrangement. It is known as yet only from Porto 
Rico. 
5. Holothuria glaberrima Selenka. 
Especially common in cavities in coral rocks on the reefs and along shore. It is rather short and 
stout, seldom more than 100 mm. long. The color varies greatly from pale yellowish brown to almost 
black, but is generally uniform over the body. The body-wall contains only scattered branching rods. 
It is found throughout the Caribbean Sea and Gulf of Mexico. Six specimens from Hucares vary in 
length from 65 to 110 mm. In five the color is blackish brown, the tentacles black; the sixth is light 
yellowish brown, with light tentacles. 
6. Holothuria grisea Selenka. 
This species reaches a length of 150 to 200 mm. The body-wall contains tables and small forked 
rods, the latter gathered in little circles or spots, often visible to the naked eye. It has been recorded 
from the West Indies, Surinam, and Brazil. Two specimens from Arroyo, 50 and 110 mm. long, and 
one from Hucares 70 mm. 
7. Holothuria impatiens Forskal. 
This is one of the most widely distributed of holothurians, being known from the warmer seas 
of all parts of the world. It reaches a length of 150 to 200 mm., and is grayish purple in color, some- 
times blotched with darker. Tentacles often very light colored. The body-wall contains tables 
and -buttons with 3 pairs of holes. From Culebra t.hei'e is one typical specimen 85 mm. long, and from 
Ponce there are two specimens (110 to 125 mm.) which are dark gray in color with no trace of purple. 
8. Holothuria mexicana Ludwig. 
This is one of the largest West Indian holothurians, often reaching a length of 450 mm. or more. 
T1 le color varies greatly; some specimens, usually small ones, are light brown above and pink or 
flesh-color beneath, the pedicels brown; others are almost jet-black with scarcely any light below. 
Between these two extremes all sorts of intergradations occur. The thick, leathery body-wall, which 
contains simple tables and numerous perforated plates of two kinds, helps greatly to distinguish this 
species. Described first from the Gulf of Mexico, and known only from the West Indian region. 
Of this very common species, there are some 20 specimens in the collection, from 110 to 300 mm. 
in length. There is great diversity in the number of tentacles and Polian vessels. Four individuals 
have 18 tentacles; six have 19; nine have 20; one has 21. Two individuals have 1 Polian vessel each; 
two have 2; five have 3; two have 4; three have 7; one has 8; one has 9. These specimens were 
collected at Culebra, Fajardo, Boqueron Bay, Guanica, Puerto Real, Mayaguez, and San Juan. 
