2 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 120 
and, as frequently happens, the specimen may be cut in two before 
the base is freed from its attachment. 
The area inhabited by this species is between the midintertidal and 
the mean lower-low water level, and they are most easily obtained by 
searching for them when there is a good minus tide. At these times 
they are commonly observed with their tentacles extended at the 
entrance to their burrow, but any movement near them will cause 
them to contract so that the body is drawn down into the burrow. 
As one starts to dig for them, they continue to contract until they 
reach one-third or less of their normal length. When the collector 
is successful in dislodging them he retrieves an anemone appearing to 
be about 10-15 cm. long and about 2 cm. in diameter at its widest 
part (exclusive of the foot). Occasionally, when too much pressure 
is applied against them in their burrows they will be seen to emit 
tiny jets of water from cinclis-lke openings in the upper column. 
We do not believe that this is a natural reaction or one that would 
occur frequently in the absence of abnormal pressure. Weak areas 
evidently occur in the upper part of the column, but histologically 
these do not appear to be typical cinclides. 
So far in the laboratory, we have not been able to relax specimens 
to anywhere near their normal length, i.e., 30-46 cm. On preserva- 
tion they tend to shorten to 15 cm. or less. 
We wish to thank both Mr. Marshall and Mr. Holleman for making 
the observations reported herein available to us. 
This work was supported by a grant from the National Science 
Foundation, GB 1237, and by a contract with the Atomic Energy 
Commission, AT (11—1)-34, Project #96. 
Family Isophelliidae 
IsOPHELLIIDAE Stephenson, 1935, p. 183. 
Thenaria (Acontiaria). Sphincter mesogloeal. Mesenteries divisi- 
ble into macro- and microcnemes; the older microcnemes may, 
however, be provided with filaments and acontia. Acontia with two 
categories of nematocysts, basitrichs, and microbasic amastigophores. 
Genus Flosmaris 
Flosmaris Stephenson, 1920, p. 441. 
Isophelliidae with the elongate column divisible into scapus and 
scapulus, the former with tenaculi. Cinclides present or possibly 
absent. Margin tenaculate. Tentacles simple, their longitudinal 
muscles ectodermal as are the radial muscles of oral disc. Sphincter 
mesogloeal; situated in upper part of scapulus. Twelve pairs of 
macrocnemes bearing gonads, though number may vary as result of 
