602 On Aquatic Carnivorous Coleoptera or Dytiscide. 
portion of the elytra is less shining than in the male, and the sculpture consists of 
short, dense, indistinct strie. 
This species seems quite intermediate between Coptotomus obscurus, and C. 
longulus. 
North America, (Massachusetts). 862. 
912. Coptotomus longulus, Lec., M.C.—Fem., Ovalis, convexus, elongatus, supra 
minus nitidus, testaceus, vertice, thorace anterius et posterius in medio, elytrisque 
vittis irregularibus plus minusve coalescentibus nigris; corpore supra densius sub- 
tiliter strigosulo, elytris versus apicem subtiliter punctatis ibidemque nitidis; 
prosterno in medio crassc, anterius perpendiculari ; coxis posterioribus magnis, 
conspicue rugoso-punctatis. Long 83, lat. 4 m.m. 
I have seen only a single female of this species; it is more elongate and nar- 
rower than that preceding, has the sculpture of the elytra denser, and that of the 
hind coxee coarser ; the interval between the middle ccxal cavities and the front 
border of the hind coxz is rather larger. 
North America, (Laramie, Nebraska, Colorado; sec. Crotch). 863. 
I. 60.—Genus LANCETES. 
Extremity of elytra sinuate-truncate. Palpi scarcely or not at all emarginate 
at the apex of the last joint: coxal processes elongate, deeply divided and much 
divergent. 
Five species* are known, three from Chili, one from southern South America, 
the other from Australia and New Zealend: although resembling in colour and 
appearance the species of Rhantus, these insects may readily be distinguished 
therefrom by the truncate elytra. 
913. Colymbetes lanceolatus, Clk., M.C.—Ovalis elongatus, aurantiaco-testaceus, 
vertice late, prothorace anterius et posterius in medio, elytris vittis elongatis nigris ; 
elytris subtiliter undulatum strigosulis, punctis seriatis conspicuis, apice subtruncatis; 
prosterno in medio anterius sub-prominulo, vix rotundato. Long. 102, lat. 5 m.m. 
The male has the basal joints of the front tarsi a good deal dilated and moderately 
* In addition to these the following probably belong to the genus. Agabus truncatipennis, Sol. (No. 
1205, huj. op.) ’=No. 915; Chil.-—Colymbetes angusticollis, Curt. (No. 1211); Chili.—Colymbetes 
rotundicollis, Bab. (No. 1245) near No. 916 ; Patagonia. 
