588 On Aquatic Carnivorous Coleoptera or Dytiscide. 
rather broad and simple. The species includes numerous forms or varieties, but 
the material before me does not justify me in considering them as distinct species. 
The female has sometimes the greater part of the elytra and the thorax at the 
sides covered with very fine anastomosing stricee, which in other specimens are 
quite wanting, and various intermediate gradations occur. ‘The size also varies a 
good deal, as does also the colour, the largest form found in Central America and 
Mexico (C. signatus, Sharp) having the red marks of the elytra pale and distinct. 
The scratches on the thorax also vary somewhat in number and depth: and the striz 
of the elytra ure also variable in depth. I have considered as the type of the species 
the form occuring in the Antilles, which was the one to which Fabricius gave the 
name Dytiscus posticatus. 
Antilles, (Cuba, Guadelope) ; Mexico; Central America; Cayenne; Brazil. 636. 
876. Copelatus terminalis, n. sp.—Ovalis, latus, depressus, nitidus, subtus rufo- 
testaceus, supra nigricans, capite, prothorace ad latera, elytris basi et apice (seepiusque 
macula laterali),antennis pedibusquetestaceis; prothorace strigulis brevibus impressis ; 
elytris striis decem subtilibus, alternis posterius abbreviatis, aliaque marginali 
brevissima. Long. 63, lat. 8: m.m. 
The male has the front and middle tarsi distinctly dilated, and the front tibise 
broad and simple; it has the thorax scattered over with short linear punctures, 
which become obsolete towards the sides, in the female these punctures are more 
elongate, and are more developed near the side than they are on the middle. 
The strize of the wing-cases are quite regular at the base, the first is a little more 
distant from the suture than it is from the second, and is carried on nearer to the 
apex than any of the others are, the alternate ones are distinctly shorter than the 
others, and nearly of one length; the submarginal stria is very short, and placed 
nearly entirely behind the middle. 
The distinct yellow marks on the elytra are variable, besides the spot near the 
side (on the 8th and 9th interstices) there is generally another on the 5th interstice, 
and this may become elongate and connected with the basal band. 
The species is very similar to a variety of Dytiscus posticatus, which resembles 
it in markings, (C. signatus, Sharp), but C. terminalis is broader, the strice of the 
elytra are finer, and the alternate ones, (especially the second), are less abbreviate 
behind. 
Central America, (8S. Geronimo, and El Jicaro, Vera Paz, Guatemala; Champion). 1162. 
877. Copelatus depressus, n. sp.—Oblongo-ovalis, parum latus, depressus, subtus 
rufo-testaceus, abdomine fuscescente, supra fusco-piceus, capite, prothorace late ad 
latera, elytris basi apiceque testaceis, antennis pedibusque testaceis; elytris striis 
