HYDROPHILIDZ. , 767 
10 (a). Berosus dispar. 
Brevis, mare nitido, femina opaca, fortiter punctatus, testaceus, capite metallescente, prothorace in medio vix fusco- 
bimaculato, elytris parce obsoleteque maculatis ; capite subtus nigricante, pectore abdomineque fusco-rufis. 
Long. 4-5 millim. 
Hab. Mexico, Chihuahua city, Mexico city (Hége). 
Head densely and coarsely punctate, with a distinct fine carina on the middle of the 
vertex; palpi and antenne pallid yellow. Thorax coarsely and rather closely punc- 
tured. Elytra deeply striate, the interstices coarsely punctured. Legs entirely yellow. 
Terminal ventral plate slightly excised, with a single angular prominence in the middle 
of the base of the excision. In the male the upper surface is shining, the basal joints 
of the front tarsi are slightly incrassate, and the apices of the elytra are quite simple ; 
the basal ventral segment is carinate throughout its whole length, and there are short 
prominences or caring on each of the following three segments. In the female the 
upper surface is opaque, owing to the existence of an additional minute punctuation, 
and the apices of the elytra are slightly prolonged, so that the sutural angle is acute ; 
the carina on the basal ventral segment scarcely extends to the hind margin, and there 
are no prominences on the following segments. Five examples. 
10 (8). Berosus debilis. 
Minor, brevis, capite prothoraceque metallescentibus, hoc flavo-marginato, elytris sordide testaceis, parce nigro- 
maculatis ; subtus niger, prothorace marginibus testaceis ; antennis, palpis pedibusque testaceis, palporum 
apice femorumque basi nigris, antennarum clava grisea. 
Long. 33 millim. 
Hab. Mexico, Tehuantepec (Hoge). 
Head and thorax rather closely and coarsely punctured, not at all rugose, metallic ; 
the latter with yellow margins, the yellow colour on the front margin irregular, owing 
to its extending farther backwards on each side of the middle, the basal yellow margin 
extremely slender. Elytra moderately deeply striate, the interstices rather sparingly 
punctured ; of a sordid yellow or griseous colour, with four small black spots on the 
disc, placed in a row longitudinally, and also with a humeral spot, and a lateral spot 
about the middle. Basal ventral segment with a carina on the middle, extending the 
entire length of the segment; apical segment with a rather deep narrow excision. 
Male with the basal joints of the front feet moderately dilated. 
HEMIOSUS (p. 84). 
Hemiosus maculatus (p. 85). 
To the locality given, add :—Mexico, La Noria in Sinaloa (Hége) ; Panama, Bugaba 
(Champion). 
A single example has been received from each of these distant localities. 
