418 On Aquatic Carnivorous Coleoptera or Di/tiscid(e. 



448. Macroponis solidus, n. sp. — Oralis, robustus, latus, minus elongatus, 

 tenuissime pubescens, crebre fortiter punctatus, subnitidus, fusco-piceus, capite, 

 thorace, elytris lateribus pedibusque minus Isete rufis, antennis fuscis, basi rufu, 

 thorace auteriu.s et posterius fusco ; coxis posteriovibus fortiter punctatis ; abdomine 

 sat evidenter punctate. Long. .5^, lat. 31 m.ni. 



1 have seen but two mules of this sj^ecies, 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 SotihiI). 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. 5t, 

 lat. vis 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 II. 

 hamatus (Xo. 44.5), 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. 



Austnilia. -118. 



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 tlie following sliould also be included in the genus : — Hydropoms angulipennis, 

 Peyr. (No. 1341 huj. op.), Group 1 ; Sj'ria. — H_ydroporus depressicollis, Ros. (No. 13G0), Group 1 ; 

 Spain. — Hydroporus dubius, AuLe (No. 13G5), 1 = No. 465 ; Africa. — Hydroporus fivirmairei, Lep. (No. 

 1370), ? = No. 456 ; Europe. — Hydroporus boristhenicus, Hoch. (No. 1347), 1 = 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. 1390); Arabia. — Hydroporus mcestus, 

 Walk. (No. 1399) ; Arabia. — Hydroporus piochardi, Regt. (No. 1415),? No. 493 var.; Syria. — Hydi-oporus 

 saiisi, Aube, (No. 1427),? No. 472 var.; Simin. — Hydroporus semiclusus. Walk. (No. 1430); Arabia. — 

 Hydroporus subtruncatus, Fairm. (No. 1438),? = No. 469; North Africa. — Hydroporus undecimHnellus, 

 Fairm. (No. 1445),? No. 490 var.; North Africa. — Hydropoms vestitus, Gebl. (No. 1448), Group I; 

 Siberia. — Hyphydrus hyperboreus, Gyll. (No. 1464),? No. 471 var.; Lapland. Perhaps also Hydroporus 

 stcarinus, Kol. (No. 1433), Caucasus, may be a Deronectes. 



