MUSEUM OF COMPARATIVE ZOOLOGY. 57 
the latter it differs in not having the upper portion of the column specialized 
and different from that below, and also in being far less contractile. Urticina 
differs in not: having the large non-adhesive tubercles, the warts, when present, 
being of the nature of adhesive suckers, and also in having the walls of the 
body and tentacles highly contractile. Bolocera differs in having the column 
smooth, or nearly so, with the tentacles long and easily deciduous. Actinernus 
differs in having the column smooth, and in having the upper margin divided 
into lobes which run up on the outer sides of the tentacles. 
Actinostola callosa Verritt. 
Urticina callosa VeRRILL, Amer. Jour. Sci., XXIII., March and April, 1882, 
pp. 224, 815. 
Plate VII. Fig. 2. 
This is, perhaps, the largest of the eight large species of actinians that in- 
habit these depths, though A. nodosa, A. longicornis, U. perdix, and Bolocera 
Tuedie grow about as large. It is also remarkable for the great number of 
short, stout, usually blant, striated tentacles. When full grown it has a re- 
markably firm, thick, leathery, but lubricous integument, and has but little 
power of contracting or rolling in the upper end. When handled it is apt to 
become irregularly flattened and collapsed, with broad longitudinal folds or 
wrinkles, while the tentacles and disk remain exposed, the very broad disk 
usually becomes deeply concave, and the tentacles contract in length and be- 
come blunt. The body usually narrows to the base, but may be hour-glass- 
shaped. The surface of the column is usually more or less covered with low, 
irregular, often flattish verruce, which become larger and more prominent, and 
sometimes form longitudial series or crests on the upper part, but fade out to 
mere wrinkles toward the base. There is no decided change in the character 
of the integument near the top, which is a conspicuous character in A. nodosa 
and A. longicornis. 
The basal disk, in large specimens, is usually bulbous or deeply concave, 
firmly grasping a large mass of sand and mud, which it often nearly encloses. 
In the mud there are often numerous chitinous pellicles, which have been 
secreted and cast off from the base, 
Large examples are often 150 to 180 mm. in height, with the expanded disk 
200 to 250 mm. (8 to 10 inches) broad; the larger tentacles are about 25 mm. 
long, 5 to 6mm. in diameter. Color generally salmon or orange, all parts often 
of nearly the same color; column almost always pale salmon or buff, varying to 
deep salmon or orange-red, with the tubercles paler; disk most often deep 
salmon, or generally of the same color as the body, but darker in shade, with 
paler radii; the large lateral lobes of the lips are like the disk, but darker, 
usually salmon or orange-brown, the large gonidial grooves whitish or pale 
yellow; tentacles usually plain deep salmon or orange-brown, with paler strie 
or reticulations. 
