418 On Aquatic Carnivorous Coleoptera or Dytiscide. 
448. Macroporus solidus, n. sp.—Ovalis, robustus, latus, minus elongatus, 
tenuissime pubescens, crebre fortiter punctatus, subnitidus, fusco-piceus, capite, 
thorace, elytris lateribus pedibusque minus lete rufis, antennis fuscis, basi rufo, 
thorace auterius et posterius fusco ; coxis posterioribus fortiter punctatis ; abdomine 
sat evidenter punctato. Long. 52, lat. 3: m.m. 
I have seen but two mules of this species, they are shorter in form, and smaller 
than that sex of Hydroporus gardnerii, and the tarsi are not quite so broad, so that 
I think the specimens indicate a distinct though very closely allied species. 
Australia, (King George’s Sound). 417. 
449, Macroporus ruficeps, n. sp.—Ovalis, minus latus, tenuissime pubescens, sat 
nitidus, crebre evidenter punctatus, piceo-rufus, capite pedibus antennisque rufis, 
elytris piceis, thorace ad latera et in medio plus minusve dilutiore; coxis 
posterioribus sat fortiter punctatis; abdomine subobsolete punctato. Long. 55, 
lat. vix 3 m.m. 
In the male the front and middle tarsi are broader than in the female, they being 
in the latter sex rather slender, the claws of the front ones are but little unequal. 
The species varies a little in colour, size and punctuation. It closely resembles H. 
hamatus (No. 445), but is smaller and more obscure in colour, rather more closely 
punctured, and with the front and middle tarsi much more slender. I have only 
seen one form of female, which differs but little from the male except in the tarsal 
structure. 
Australia. 418. 
I. 40.—Genus DERONECTES. 
The ridge on inner face of wing-case is destitute of a ligula ; the posterior portion 
of the epipleura is narrow, and the humeral area is not limited externally by a 
raised line. The mesosternal fork does not connect with the intercoxal process of 
the metasternum. 
Most of the numerous species* (about 45) inhabit the European and Mediterranean 
regions, very few North America. They form four groups defined as follows :-— 
*In addition to these the following should also be included in the genus :—Hydroporus angulipennis, 
Peyr. (No. 1341 huj. op.), Group 1; Syria—Hydroporus depressicollis, Ros. (No. 1360), Group 1; 
Spain. —Hydroporus dubius, Aubé (No. 1365),?= No. 465; Africa.—Hydroporus fairmairei, Lep. (No. 
1370), ?=No. 456 ; Europe.—Hydroporus boristhenicus, Hoch. (No. 1347),?=No. 472 var.; Europe.— 
Hydroporus inconspectus, Lep. (No. 1380),?= No. 456 ; Europe.—Hydroporus infaustus, Clk. (No. 1384), 
near No. 494; Mexico.—Hydroporus lanceolatus, Walk. (No. 1890); Arabia.—Hydroporus meestus, 
Walk. (No. 1399) ; Arabia.— Hydroporus piochardi, Regt. (No. 1415),? No. 493 var.; Syria.—H ydroporus 
sansi, Aubé, (No. 1427),? No. 472 var.; Spain.—Hydroporus semiclusus, Walk. (No. 1430); Arabia.— 
Hyavoporus subtruncatus, Fairm. (No. 1438),?=No. 469; North Africa.—Hydroporus undecimlinellus, 
Fairm. (No. 1445),? No. 490 var.; North Africa—Hydroporus vestitus, Gebl. (No. 1448), Group I; 
Siberia.—Hyphydrus hyperboreus, Gyll. (No. 1464),? No. 471 var.; Lapland. Perhaps also Hydroporus 
stearinus, Kol. (No. 1433), Caucasus, may be a Deronectes. 
