1853.) 2 
bo 
bo | 
Ampuizoa Lec. (Fam. nova ?) 
Pedes ambulatorii, tarsi pentameri, articulo ultimo valde elongato; antenne 
11-articulate, filiformes, glabra; palpi breves cylindrici; maxilla lobo interiore 
arcuato acuto, exteriore biarticulato, palpiformi; prosternum postice productum, 
obtusum; coxe antice et intermedie parva, globose, postice transverse ad mar- 
ginem corporis extense ; abdomen 6-articulatum, articulis 3 primis connatis. 
After repeated comparisons with genera of all the families to which this in- 
sect seems allied, it has been found impossible to place it in any of the pre- 
viously establis jivedl groups. A full discussion of the comparative value of the 
characters offered by it, would involve an examination of the fundamental prin- 
ciples of classification Of the terrestrial and aquatic predacious beetles ; the ma- 
terial for such a discussion is not yet available in this country, and it must 
therefore be postponed to a future occasion. For the present, a few observations, 
on some heretofore neglected relations existing between those families, will be 
sufficient to indicate the position of Amphizoa. 
A large series of pentamerous, carniverous Coleoptera, may be characterized 
as* having the antenne neither clavate nor lamellate, but usually filiform, and 
the prothorax with distinct epimera and episterna; the anterior cox small, not 
prominent, usually globular; the trochanters always simple; the anterior seg- 
ments of the abdomen connate. This series may be divided into two great groups. 
I. In the first the anterior coxe are contained in the prosternum alone; the 
posterior coxe do not extend to the margin of the body, so that the first ventral 
segment of the abdomen reaches the parapleure, and articulates with them. 
(The antenne are always regular, the basal joints glabrous, the outer ones 
pubescent; the anterior coxe always globular.) This group consists of the 
Cicindelide and Carabide. 
II. In the second, the anterior coxe are received between the pro and mesos- 
ternum, the posterior portion of the acetabulum being composed of the latter ; 
the posterior cox extend to the margin of the body, so that the connection 
between the parapleure and first ventral segment of the abdomen is entirely 
cut off. This group is composed of the aquatic families Haliplide, Dytiscide, 
and Gyrinidex. 
Recurring now to the second group, it will be found that Amphizoa agrees 
with it in the glabrous antennae, and in the form of the head, labrum, maxillx 
and mentum; the latter is large, deeply emarginate, with the lateral lobes 
rounded ; in the middle of the emargination is a broad, short, blunt tooth. The 
ligula is large, filling the emargination of the chin, truncate at tip, and promi- 
' nent along the middle and apex, so as to present a form like the letter T. The 
maxille are of the ordinary form seen in Carabide, but the inner lobe is not 
ciliated. The prosternum is not elevated, it is not lobed in front, but poste- 
riorly is produced in an obtuse spatula-like process, fitting into the mesoster- 
num, which is excavated through its entire length; the anterior coxe are mode- 
rately distant, small and round. The episterna are divided by an oblique suture 
from the humerus to the middle coxw. The parapleure are slightly triangular, 
not appendiculate, and entirely separated from the ventral portion of the abdo- 
men by the posterior coxe, which are transverse, flat externally, slightly 
elevated and diverging at the insertion of the leg, as in Carabide ; the diverg- 
ing lobes are obtusely rounded, but not so much elevated as to allow the freedom 
of motion observed in Dytiscide. The legs are not at all compressed ; the femora 
and tibiz are slender and finely scabrous, with elevated points, the terminal 
spurs of the tibiz are small; the tarsi are three-fourths as long as the tibia, 
filiform, glabrous, scarcely rough or pubescent beneath; the first four joints are 
equal, the last joint is equal to the three preceding united ; the claws are mode- 
rate, equal and simple. 
It will be found in comparing these characters with those of Dytiscus, that 
the only important differences are in the form of the feet, and in the smaller 
size of the posterior coxe. Now, although the Dytiscide and Haliplide, which 
are certainly closely related, agree in having natatorial feet, they differ greatly 
in the modification of form, those of Haliplus being much nearer the terrestrial, 
