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PACIFIC SCIENCE, Vol. Ill, October, 1949 
in the fish traps. The shells were covered over 
the outside and about the aperture by a large 
and fairly common species of sea anemone, 
Calliactis armallatas Verrill ( Sagartidae ) . Al- 
though many of the specimens are not in perfect 
condition, the characteristics of all of them show 
well enough to permit identification. 
Distribution: Indo-Pacific area and the Ha- 
waiian Islands. The occurrence of this species 
in Hawaiian waters is believed to be unrecorded. 
A series of more than 25 specimens from the 
southwestern shore of Oahu has been studied. 
The Hawaiian specimens from this locality have 
been distributed to permit their widest use and 
may now be observed in the following collec- 
tions: the United States National Museum in 
Washington, D. C., the Science Museum of the 
California Academy of Sciences in San Fran- 
cisco, and in the collections of the Bernice P. 
Bishop Museum, Ditlev Thaanum, Dr. C. M. 
Burgess, Dr. Vernon Smith, Arthur Wriston, 
Charles Allen, and the author, all of Honolulu. 
Tonna canaliculata Linnaeus 
Description: Shell ovate, large, thin, hard, 
greatly expanded; whorls about seven in num- 
ber; body whorl greatly expanded centrally, en- 
circled by about 19 broad, closely set, flat, spiral 
ribs, separated by comparatively narrow and 
shallow interspaces, marked at the sutures by 
a deep channel; columella reasonably straight, 
but slightly twisted; lip simple; color tawny 
yellow exteriorly, ribs lighter in color, grooves 
darker, body whorl becoming increasingly 
darker toward the lip; length, 3 to 5 inches. 
Ecology: This species is the rarest of the tun 
shells in Hawaiian waters, being known in this 
locality from a single specimen. It is apparently 
entirely absent in shallow water and very rare 
at depths of less than 100 feet. The single 
specimen was occupied by a hermit crab which 
had carried it into a wire fish trap at a depth 
of about 15 fathoms. 
Distribution: Indo-Pacific area including the 
Hawaiian Islands. The occurrence of this species 
in Hawaiian waters is based upon a single speci- 
men from the southwestern shore of Oahu in 
the collection of the author. This is believed 
to be the first record of this species from the 
Hawaiian Islands. 
Genus Malea Valenciennes 
Shell ovate, thin, hard, relatively heavier; 
whorls less expanded; umbilicated; outer lip 
simple, outwardly reflected, dentate; aperture 
reduced. 
A single species is known from the Hawaiian 
Islands. 
Malea pomum Linnaeus 
Description: Shell ovate, comparatively thin 
and hard but less so than in genus Tonna; 
whorls about six in number; body whorl mod- 
erately large and expanded, but less than in 
Tonna, encircled by about 12 well-defined, low, 
spiral ribs; spire short; sutures not depressed; 
outer lip dentate within, reflected flatly out- 
ward, somewhat thickened; columellar lip den- 
ticulate or wrinkled; columella very slightly 
excavated at the base; color white, marked with 
amber of varying intensity and arranged so as 
to appear spotted with white upon the ridges; 
lips white; length, 1 to 3 inches. 
Ecology: This species is the smallest tun shell 
in Hawaiian waters and the third most abun- 
dant, being exceeded in numbers by T. perdix 
and T. melano stoma. It is most abundant at 
depths approaching 100 feet but is occasionally 
taken in shallower water. It is apparently not 
as readily sought out by hermit crabs as are 
the larger species possibly because the dentition 
of the shell reduces the aperture and restricts 
movement, or because the shell is heavier to 
carry and less easily trimmed at the lip to fit 
the needs of the crabs. 
Distribution: Indo-Pacific area from the Red 
Sea to eastern Polynesia and the Hawaiian 
Islands. 
The author acknowledges with pleasure the 
assistance of Dr. Harald Rehder, Ditlev Thaa- 
num, and Wray Harris in problems of distribu- 
tion and taxonomy, and the help of Charles 
Allen, Mrs. Ruth Porter, Kenneth Wong, and 
Wing You Tong in the preparation of the 
photograph. 
