12, Report on the Parasitic Copepoda collected during 
the survey of the Juan Fernandez Islands, 1916—1917. 
By 
GHARLES’ BRANCH WILSON; D:-Se,/Pky D: 
State Normal School, Westfield, Massachusetts. 
With Plates 2—4. 
Introductory. During the survey the zoologist, Mr. K. BACKSTROM, 
collected five vials of parasitic copepods which, upon examination, prove to 
be of peculiar interest. 
In the first place they come from a region where very little collecting 
has ever been done. The eastern portion of the southern Pacific is virtually 
unknown, as far as its copepod parasites are concerned. The present lot are 
the first to be obtained from these particular islands, and practically the first 
from the entire region. 
Then the hosts upon which they were found are exceptional, the large 
scombrid, the white-spotted cabrilla, the little clingfish, the curious wreckfish, 
and the Chilian sculpin. It is not strange, therefore, that three and probably 
four of the vials should prove to be new species, and that one of them con- 
stitutes a new genus. 
The specimens are all deposited in the Museum of Natural History at 
Stockholm, Sweden. 
Juanettia, new genus. — Plate 2; 3 fig. 7. 
Generic characters of female. Head fused with the first thorax seg- 
ment, and the two separated from the second segment by a short neck; a pair 
of fleshy bifurcate processes on the ventral surface at the posterior corners of 
the cephalothorax. Second, third, and fourth thorax segments distinctly separ- 
ated, each with a lateral cylindrical process on either side. Second segment 
with a pair of large conical horns on the dorsal surface at the anterior margin; 
egg strings cylindrical, multiseriate. First antennae enlarged and fleshy at the 
base; second pair modified into stout prehensile hooks. Mandibles toothed on 
