FISH PARASITES COLLECTED AT WOODS HOLE. 
279 
22. Palinurichthys perciformis, Rudder-fish. 
(1) Angus! 10; one, small; stomach contents not noted. An enormous number of small distoma 
on and in the pyloric c;eca, Distomum pyrif ovine. See page 292 for description. 
(2) August 19; six; stomach contents not noted. Larval cestodes in general similar to forms 
found in squeteague, flounder, goose-fish, etc., in intestine, but very small. Dimensions of living 
specimens, in millimeters: Length 0.34, breadth 0.17; specimen with head invaginated, length 0.26, 
breadth 0.14. A few small distoma, D. pyriforme, in intestine. 
Echinorliynchus pristis, var. tenuicornis (Entozoa of Marine Fishes, hi, pp. 531-532, pis. IV, 
figs. 39-41; v, figs. 42-53); from intestine, one. 
One small immature nematode also found, from intestine. 
(3) August 22; three; stomachs contained small univalve shells ( Trittia trivitata), and the slender 
crustacean, quite common among livdroids (Caprella geometrica). Larval cestodes, and numerous small 
distoma, as in lot examined August 10. These entozoa were from the alimentary canal in the vicinity 
of the pyloric cmca. 
(4) August 25; four; stomachs contained young squid (Loligo pealii), Crustacea. Larval cestodes 
and small distoma, as in preceding lots, obtained by opening the alimentary canal, and washing con- 
tents iu a dish of sea water. One of the former appeared to have a more prominent myzorhynchus 
than usual. 
23. Rhombus triacanthus, Butter-fish. 
(1) July 21; one; stomach contents not noted, probably empty. Numerous immature nematodes 
on viscera. 
(2) July 23; one; stomach contents not noted. One small cyst containing blastocyst and larva 
CRhyncliobothrium), and enormous numbers of immature nematodes on and among the pyloric cseca. 
The combined bulk of the worms appeared to be almost equal to that of the pyloric caeca. 
(3) August 10; three ; stomach contents not noted. Serous coat of pyloric caeca with large 
numbers of immature nematodes. 
(4) August 22; four; stomach contents not noted. A few small cysts and numerous small, 
immature nematodes found on pyloric caeca. 
24. Morone americana, White Perch. 
August 27; three, small; stomach full of shrimps. 
Distomum areolatum Rudolphi. See page 293 for description; rather numerous, found in dish in 
which viscera had been lying. 
Numerous pigment patches on viscera generally, especially on liver, but also abundant on 
mesentery, stomach, and intestine. A study of the tissue affected with these patches confirmed certain 
conclusions recorded in my Notes on Trematode Parasites of Fishes, page 537. 
Large numbers of cysts in various stages of degeneration were found. In most of them ova, which 
are without doubt the ova of some distomum, formed the nucleus of the cyst. These ova measured 
about 0.020 aud 0.013 mm. in the two principal diameters. They therefore do not belong to D. areo- 
latum. The principal steps in the degeneration of the cysts to pigment were represented by, (a) one 
or more ova with cyst of connective tissue just beginning to form, (6) others with cyst of connective 
tissue fully formed, (c) others with cyst and the contained ovum or ova surrounded with a waxy 
secretion, (d) a waxy mass with no ova visible, also masses of dark-brown, almost black pigment. 
Sections of the liver were made, but no pathological conditions were noted further than the presence 
of pigment patches in the serous coat, some of which contained large numbers of ova; 6,400 estimated 
in one patch through which sections were made, and about half of them mounted serially. 
25. Centropristes striatus, Black Sea-bass. 
(1) July 28; one; stomach empty. The fish had been in an aquarium for several weeks. The only 
parasites found were numerous small cysts containing larval cestodes in the submucosa of the stomach. 
See page 301 for supplementary note. 
(2) August 5; one; stomach with a few small fish nearly digested. The fish was taken from an 
aquarium where it had been kept for several weeks. A few cysts on the mesentery and under the 
serous coat of the liver. One of the cysts when opened released a blastocyst to which the larval 
