On Aquatic Carnivorous Coleoptera or Dytiscide. 319 
serrulatis, pone medium subsinuatis, angulis posterioribus subrectis, medio longi- 
tudinaliter canaliculato ; elytris punctato-rugulosis, sat distincte striatis ; prosterni 
processu sat elongato. Long. 12%, lat. 6 m.m. 
I have seen only a single individual of this species, which is closely allied to A. 
insolens, but has the hind angles of the thorax less acute; the elytra are more 
elongate and less convex, and the prosternal process is more elongate and parallel 
sided. The legs are longer than in A. insolens, and though the tarsi are broken 
off from the individual, except the two basal joints of the posterior ones, these are 
much longer than in A. insolens. 
North America ; (Vancouver's Land.) 233. 
178. Amphizoa lecontei, Matthews, Cist. Ent. I. p. 121.—Rufo-nigra vel picea, sine 
pubescentia ; cpaca, obsolete rugulosa ; thorace elytris multo angustiore, lateribus 
obsolete serratis, pone medium haud sinuatis, angulis posterioribus subobtusis, 
basi recte truncato, medio longitudinaliter canaliculato ; elytris ampliatis, minus 
fortiter rugulosis, minus distincte striatis, longitudinaliter subcostatis, epipleuris 
latis; prosterni processu anterius elongato. Long. 123 lat 73 m.m. 
This species is readily distinguished by the broad elytra, which are longitudinally 
subcostate, and have their inflexed part much broader, and by the tact that the 
edges of the prosternal process are continued forwards beyond the front cox 
towards the front edge of the thorax, which however they do not nearly reach. 
North America ; (Vancouver's Land.) 234. 
Ill. 2.—Trbe HY DROPORIDES. 
Prosternum deflected between the front coxze, so that the prosternal process has 
a different plane of direction from that of the prosternum. Front tarsi usually four- 
jointed (five-jointed in Sternopriscus, Necterosoma and Celina). ‘Scutellum usually 
quite concealed (but exposed in Celina). 
This is the most extensive tribe of the Dytiscide. 
Posterior coxal | 
cavities widely 
separated; each | 
win lng, ar i = Hyprovartini. 
coxal excision, | (Vide p. 320.) 
andextrarimal 
lobe. \ 
