M. Hesse on a new Parasitic Crustacean. 81 
(and this is a special character of the Lerneida), that there 
exists all round the body a transparent border, which accompa- 
nies its outline through all its cireumvolutions. 
Moreover a circumstance which has no less attracted our at- 
tention, and which, in our opinion, is most curious, is the resem- 
blance existing in the mode of life of the two parasites. 
We know, in fact, that Lernea branchialis, by means of its 
buecal apparatus, which, as in our parasite, does not appear to 
furnish any resources for this purpose, and which appears rather 
destined to draw up liquid materials by suction, succeeds never- 
theless, in course of time, in perforating the very thick and re- 
sistant first wall of the branchial arch of fishes, in order to lodge 
its radiciform frontal system in the space occurring between the 
two plates of this bony part. Our parasite, by similar actions, 
also, by separating and raising the two lamine which form the 
scales of the fish on which it has established itself, succeeds in 
altering their structure, thus creating for itself a refuge in which 
it is entirely lodged, and where it lives in peace and sheltered 
from all dangers. 
From what has gone before, and notwithstanding the differ- 
ences existing between the two species which we compare, we 
do not hesitate to thik that they must belong to the same 
order; and we form for our parasite a new family, which we 
characterize as follows :— 
Family Lernzosiphonostomea. 
The females fixed upon their victim by means of the scales 
of the latter, in which they hollow out a residence. Several 
footjaws placed around the mouth. Head not horned. Ovi- 
ferous pouch large and flat. 
Genus LrerosPHitus*, nobis. 
Body fusiform, divided into ten [eleven] segments, which are 
very distinct, with the exception of the third and fourth; of 
these, four [five] are thoracic and six abdominal ; all surrounded 
by a transparent border. Head small, rounded at the apex, bear- 
ing above a median eye, and beneath presenting the buccal 
orifice, which emits, in a proboscidiform process, some denticu- 
lated jaws adapted for the trituration of objects, and laterally three 
pairs of prehensile footjaws. Antenne very small, rounded at the 
end, and terminated by divergent hairs. Abdominal segments 
retractile, and capable of invagination ; last segments terminated 
by divergent appendages. Embryo ovulate, furnished with three 
* This name ought evidently to be Lepidophilus, and the specific name 
Labri, instead of Labret. 
