576 On Aquatic Curnivorous Coleoptera or Dytiscide. 
843. Copelatus alternatus, n. sp.—Ovalis, subdepressus, angustulus, nitidus, piceus, 
capite, prothoracis lateribus elytrisque castaneis, his basi dilutiore ; thorace strigulis 
numerosis distinctis sequaliter distributis; elytris striis decem haud_ subtilibus, 
alternis evidenter brevioribus. Long. 6, lat. 2? m.m. 
In the male the front and middle tarsi are moderately dilated, the front tibize are 
rather stout, and very indistinctly emarginate below the knee. In the female the 
upper surface bears rather numerous very fine punctures which are not to be observed 
in the male. The females show a good deal of variation in the prothoracic scratches, 
these in the individuals from Petropolis being finer and less numerous than in the 
specimens from other localities; I have seen but a single male and four females. 
South America, (Brazil). 639. 
844. Copelatus duponti, Aube, M.C.—Ovalis, subdepressus, nitidus, subtus rufo- 
piceus, supra rufescens, prothorace medio late nigricante, elytris lateribus fasciaque 
lata transversa pone medium nigris ; prothorace strigulis parcis distinctis sed brevi- 
bus ; elytris striis decem subtilibus, quarum secunda quam ceteris versus apicem 
paulo brevior, antennis pedibusque rufis. Long. 63, lat. 33 m.m. 
In this species the elytra are of an obscure yellowish or reddish colour, with a dark 
mark extending along the side but not reaching the extremity, this mark is broader 
near the shoulder, and beyond the middle is connected with a dark mark which 
extends inwards but does not reach the suture. In the male the front and middle 
tarsi are moderately dilated, the front tibize are rather stout and simple. In the 
female the sides of the thorax bear numerous dense fine stria, in addition to those 
that are distributed over the rest of the surface. 
South America, (Cayenne, Petropolis, Decr., 1850, R. F. Sahlberg.) 638. 
845. Copelatus bonvouloiri, n. sp.—Fem., Robustus, ovalis, sat latus et elongatus, 
nitidus, niger, capite, prothoracis lateribus anguste, elytrorum basi et apice, antennis 
pedibusque rufis, corpore subtus piceo; prothorace undique dense strigoso ; elytris 
striis decem subtilibus, alternis (preesertim secunda) brevioribus. Long. 7, lat. 
33 mM.m., 
Readily distinguished amongst its allies by the very dense and distinct scratches 
on the thorax and by its large size: the red colour at the base of the elytra is not 
extensive and therefore not very striking, on the other hand the yellowish apex 
is very conspicucus. 1 have seen only a single specimen. 
South America, (Brazil, Sta. Catherina, coll. Bonvouloir.) 647. 
