104 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
155. Balistes carolinensis Gmelin. Trigger-fish ; Leather-jacket, (t §) 
Very rare; not taken every year. Young not observed. 
156. Canthidermis asperrimus (Cope). Sobaco. (§) 
A specimen of Canthidermis taken in the summer of 1897 is identified as Balistes asperrimus of Cope, 
the type of which, belonging to the Philadelphia Academy of Natural Sciences, has been examined. 
The type is 3 inches long and is labeled “ Darien” (Isthmus of Panama); no other specimens are 
known, unless this fish should prove to be the young of Poey’s Balistes sobaco from the West Indies. 
The Woods Hole example is If inches long, and was obtained July 24, 1897, under a small piece of 
floating gulf-weed in Vineyard Sound off Great Harbor. 
MONA.CANTHIDJE. The File-Fishes. 
157. Monacanthus hispidus (Linnaeus). Foolfish; Filefish. (* t §) 
Present every year ; some years rather scarce, some years abundant. In 1897 it was extremely 
numerous in July and August, and several hundred were often taken in one day in the collecting seine. 
May often be obtained under gulf- weed, but usually most plentiful in eelgrass and rockweed. No 
large fish are observed; the maximum size is under 4 inches, and the smallest is 1 inch. The smallest 
filefish are rather uniformly dull brownish or greenish yellow in color, but those 3 or 4 inches long are 
mottled with white and several shades of dark green. In aquaria, small filefish often annoy and 
injure other fish, following them with great persistency and biting their fins, eyes, and other parts. 
Fish many times larger than themselves are sometimes the object of their attack. 
158. Alutera schoepfii (Walbaum). Foolfish; “Filefish.” (* t ()) 
Rather common every year in August and September. The largest are 18 inches long, the smallest 
3 inches. The position constantly assumed in the aquarium is with the head down. Succulent 
algae are often eaten by the fish in captivity, the long branches of some species being bitten off and 
swallowed in a surprisingly short time. The color of the young is a dirty white, with large reddish- 
brown mottlings or blotches ; the larger are orange-colored with same mottlings as when young. 
OSTRACIIDiE. The Trunk-Fishes. 
159. Lactophrys trigonus (Linnaeus). Trunhfish ;■ Shellfish. (* §) 
Adult trunkfish have not been observed in this vicinity, but the very young are not uncommon 
and are taken every year. They are found from July to October. On quiet days they are seen, singly 
or in scattered bodies, in the eelgrass about the wharves. The largest specimens in the collection are 
1 inch long, and the smallest one-fourth inch. They are taken under the gulf- weed, in surface tow 
nets and in shore seines. Several dozen have been obtained at one seine-haul. 
TETRAODONTIDiE. The Puffers. 
160. Lagocephalus lsevigatus (Linnaeus). Smooth Puffer; “Puffer.” (*t) 
Not very common. Perhaps half a dozen are taken each year in traps in Buzzards Bay and 
Vineyard Sound, mostly in September and October. All are about 11 or 12 inches long, small ones 
never being observed. 
161. Spheroides maculatus (Bloch & Schneider). Swellfish; “Puffer.” (t§) 
Appears about first of June, and is abundant during the run of soup ; many caught in traps at that 
time. Common throughout the summer at head of Buzzards Bay, but rare at Woods Hole during that 
season. Leaves in fall as soon as cold weather sets in. The spawning season is June 1 to 10. The 
largest are 7 inches in length, but the average size is 5 inches. From about July 1 to October 15 
the young, from f inch to 1 inch long, are extremely abundant at Woods Hole, frequenting chiefly 
sandy beaches, where as many as a hundred are often taken in one seine-haul. 
162. Spheroides spengleri (Bloch). Southern Puffer; Sivelltoad. (*) 
Very rare. A number of small specimens taken in September and October, 1877 ; not recently 
detected. 
DIODONTIDAl The Porcupine-Fishes. 
163. Diodon hystrix Linnaeus. Porcupine-fish. (§) 
A very rare straggler, being taken only once. On August 12, 1895, a specimen, 9 J inches long, 
was obtained in Buzzards Bay near the station. 1 
See Rept. U. S. F. C. 1896, p. 173. 
