BARBADOS-ANTIGUA EXPEDITION 197 
common in the eel-grass of Falmouth Harbor along with Dia- 
dema, Toxopneustes variegatus, and Tripneustes esculentus. In 
this shallow water, which became quite warm at noon, were 
quantities of Manicina, and curiously enough, Millepora alci- 
cornis of the most branched form. The animals are superlative- 
ly sluggish in daytime. The bottom upon which they live is of 
very fine sand or mud, often slimy with organic matter, and the 
fine particles adhere to the skin of the holothurians, giving them 
sometimes a dusky hue. A form of this species, or possibly a 
distinct species, has a vermilion pink ventral surface. In the 
aquaria at night the animals were more active than in the 
same situation during the day. 
The alimentary canal of a number of failures at anesthetiz- 
ing—to-wit, of specimens which eviscerated— was full of the 
fine silt of the Harbor, but this was true of all species. I 
watched these animals in their native haunts and I failed to find 
one crawling about.. All seemed to maintain a peevish reserve, 
due, I think, to the irritating effects of the brilliant light. 
Holothuria captiva Ludwig. A small brown, very warty spe- 
cies about 1144 to 21% inches long, found abundantly under 
stones at Harbor Point in the same locality as H. surinamensis, 
and very sparingly under stones at Falmouth Harbor. It has 
bright yellow tentacles and shoots out the delicate viscid Cuvier- 
jan organs with great freedom and precision. It was the only 
species that did this trick. This form was very active in cap- 
tivity. It is found under rocks that rest against rocks, rather 
than the sand; and the water, again, is very perceptibly heated 
when the tide is out. A small spider crab which was ‘‘shot up’’ 
with the Cuverian filaments, was visibly embarrassed as the 
threads stretched out at each movement of his legs. He solved 
the difficulty, however, by eating the threads. 
Holothuria glaberrima Selenka. A very dark brown, almost 
black species, with large, practically dendritic tentacles and a 
mass of small crowded tube-feet, as many as the ventral surface 
will hold. This species is found only on the rocky shores ex- 
posed to the buffeting surges of the open sea. It lives in minia- 
ture basins of the rocks associated with Echinometra lucunter. 
These little hollows seem to be the ‘‘forms’’ once occupied by 
Echinometra. When the tide is out, the hollows retain usually 
