On Aquatic Carnivorous Coleoptera or Dytiscida. 499 
675. Agabus lugens, Lec., M.C.—Ovalis, latiusculus, niger, supra subzenescens, 
omnium densissime reticulatus, subnitidus, antennis palpis pedibusque piceis, elytris 
versus latera gutta elongata, subdistincta, testacea ; prothorace brevi basi elytrorum ~ 
latitudine, lateribus obliquis, angulis posterioribus fere rectis. Long. 94, lat. 52 m.m. 
In the male the front and middle tarsi have the three basal joints distinctly 
thickened and furnished beneath with glandular hairs ; the claws are simple. The 
species is very closely allied to Agabus perplexus, but the reticulation of the elytra 
is so dense and indistinct that, even towards the apex, distinct meshes can scarcely 
be perceived. 
North America, (California, Vancouver’s Island). 729. 
676. Dytiscus biguttatus, Ol., Agabus biguttatus, M.C._—Oblongo-ovalis, niger, 
nitidus, antennis rufis, apice summo szepius nigro, palpis piceo-rufis; elytris guttis 
duabus testaceis; prothorace basi curvato, lateribus plus minusve curvatis et 
antrorsum angustatis, margine laterali haud crasso; elytris ad basin et ad suturam 
vel omnino leevigatis, vel omnium subtilissime reticulatis, versus apicem subtiliter 
vel vix conspicue rugulosis et paulo conspicuius reticulatis. Long. 9, lat. 48 m.m. 
In the male*the three basal joints of the front and middle tarsi are distinctly 
incrassate and furnished beneath with glandular hairs, and the anterior claw of 
the front foot has a tooth or lobe in the middle beneath. There is a sexual difference 
in sculpture the female being a little less shining, and less indistinctly reticulate 
than the male. 
This is a very widely distributed and one of the most variable species, and the 
variations seem to be, to a greater or less extent, geographical. The elytra, in the 
South-east of Europe and Asia Minor, are frequently more or less red. ‘The largest, 
broadest and most smooth individuals occur in Southern Europe. ‘The variety from 
the Canary Islands (A. consanguineus, Woll.) has the reticulation of the upper 
surface more distinct, and the antennz immaculate at the apex, the legs and palpi 
of rather more dilute colour. The species in Scotland makes a nearer approach in 
form and sculpture to Dytiscus guttatus (No. 670) than it does elsewhere, and this 
form is approximated by mountain specimens even from the South of Europe. 
The tooth on the front claw of the male varies much, being sometimes quite slender, 
and in other cases a broad lobe. 
Central and Southern Europe, North Africa, Western and Central Asia. (Scotland, England ; Belgium, 
Alsatia, France, Spain, Sierra Nevada 7,000 feet; Italy, Sicily, Greece; Canary Islands; Algeria, 
Egypt, Nubia, Sinai ; Hedjaz ; Trebizond ; Turkistan, Dras, Kargil and Leh, F. Stoliczka, September 
9th, 1873). 731. 
677. Agabus heydeni, Wehncke, Berl. Ent. Zeit. XVI, p. 134.—Ovalis, politus, 
nitidus, niger, antennis palpisaue rufis, pedibus piceo-rufis: elytris pone medium 
TRANS. ROY. DUB. SOC., N.S., VOL. II. 3 7T 
