MUSEUM OF COMPARATIVE ZOOLOGY. 45 
ACTINARIA. 
Adamsia sociabilis Verritt. 
Adamsia sociabilis VERRILL, Amer. Jour. Sci., XXTII., March, April, 1882, pp. 225, 
314, 815. 
Plate VIII. Figs. 2, 3. 
Column slender and long in full expansion, very changeable, smooth, with 
pores (cinclide) near the base; disk a little wider than the column; tentacles 
small, slender, in two circles, often held alternately erect and recurved. Mouth 
often protruded. 
Color of column translucent, and usually conspicuously striped with alternate 
pink and flake-white lengitudinal bands, the latter narowing upward; tenta- 
cles pinkish; mouth with pink lips, crossed by darker lines, between the 
small lobes. Height in expansion, about 10 to 14 mm. 
This species is always carried about by a small hermit-crab (Catapagurus 
socialis Smith, formerly Hemipagurus), as represented in our figure. 
It starts upon a small shell, usually Cadulus, or a pteropod (Cavolina), occu- 
pied by the crab when young. The base becomes much expanded and bilobed, 
the lobes often surrounding the aperture of the shell, and uniting beneath. 
The basal disk, as it enlarges, secretes a thin greenish or brownish chitinous 
pellicle, which covers the shell and extends far beyond its aperture, thus in- 
creasing the space for the crab. Eventually the shell is usually entirely dis- 
solved or absorbed, and in its stead there is only the conical or hood-shaped 
horny pellicle, in which the crab protects his abdomen. The crab is an active 
species, and habitually exposes more of its body than is usual in the group. It 
is probably able to swim free. The disk of the actinian, usually, if not always, 
is held downward, beneath and behind the legs of the crab. This position 
would be favorable for obtaining its share of the food, when the crab is eating. 
This species was taken by the Blake, at Station 344, in 129 fathoms, 
N. Lat. 40° 1’, W. Long. 70° 58’. 
It was taken off Martha’s Vineyard, at many stations, in 76-410 fathoms, 
by the U. S. Fish Commission, in 1880, 1881, and 1882. 
Sagartia abyssicola Verri tt. 
2 Phellia abyssicola Koren & Dan., Fauna Litt. Norvegiz, III., 1877, p. 78, pl. 9, figs. 
3, 4. 
Sagartia abyssicola Verritu, Amer. Jour. Sci., XXTII., 1882, pp. 314, 315. 
Plate VI. Figs. 1,1 b, 1c. 
Base broad, adherent, expanded and thin at the edges, often clasping the 
tubes of Hyalinecia artifex, and also attached to pebbles and shells. Column 
