64 4 On Aquatic Carnivorous Coleoptera or Dytiscide. 
999. Dytiscus latro, n. sp—EHlongatus ; subtus testaceus, nigro-variegatus, supra 
niger, prothorace limbo omni elytrisque flavo-marginatis, antennis pedibusque rufis ; 
prosterni processu sat elongato ; coxarum processubus prolongatis, angustatis et 
acuminatis. Long. 31, lat. 16 m.m. 
This species is imperfectly known to me by a single individual, which is an 
unsulcate female ; it is however undoubtedly distinct ; it has the comparatively 
elongate and slender form of D. circumflexus, and its coxal processes are inter- 
mediate between those of D. dauricus and D. circumflexus, being shorter than in 
the latter, longer than in D. dauricus; the female is however readily distinguished 
from the unsulcate females of both of the species alluded to by the great develop- 
ment of the punctuation on the wing-cases; this punctuation is rather regular as 
in D. circumflexus, but is much coarser and has a much greater extension towards 
the base of the elytra. 
Mantchuria. 948. 
1000. Dytiscus piceatus, n. sp.—Elongatus ; subtus testaceus, metasterno in 
medio nigricante, supra capite thoraceque nigris, hoc flavo-marginato, elytris rufes- 
centibus, flavo-marginatis ; prosterni processu sat elongato ; coxarum processubus 
prolongatis, abrupte angustatis, acuminatis. Long. 33, lat. 16 m.m. 
This species is known to me only by a single male individual ; it 1s extremely 
similar in form to D. circumflexus, and has the small palettes of the dilated tarsi 
just asin that species; the colour of the elytra is however reddish, the undersurface 
is but little marked with black, and the coxal processes are different in form, being 
rather less elongate than in D. circumflexus, but they are more abruptly narrowed, 
so that their slender portion is more clearly marked off, somewhat as in 1D. 
lapponicus. The punctuation of the apex of the elytra is but slight, even less in 
fact than in D. circumflexus. 
Eastern Siberia ; (Irkutsk). 949. 
1001. Dytiscus circumflexus, Fab., M.C.—Elongatus; subtus testaceus, nigro- 
fasciatus, supra olivaceus, vel viridi-olivaceus, scutello flavescente, prothorace limbo 
omni elytrisque flavo-marginatis; antennis pedibusque rufis, tarsis posterioribus 
plus minusve picescentibus ; prosterni processu sat elongato ; coxarum processubus 
valde elongatis, attenuatis, et acuminatis. Long. 33, lat. 162 m.m. Long. 272- 
35 m.m, 
Mas, nitidus, elytris ad apicem parum punctatis. 
Fem. (a), subopaca, elytris ad basin ultra medium sulcatis, ad apicem crebrius 
eequaliter punctatis, prothorace undique crebre subtiliter punctato. 
Fem. (b), nitida, elytris ad apicem sat punctatis, prothorace in medio subtilissime 
punctato, ad latera subopaco et paulo fortius punctato. 
