Coleopterological Notices, V. 487 



transversely fusiform spoDgiose line at the angle separating the 

 vertical from the upper portion, and is invisible from above. The 

 large sixth antennal joint is deeply excavated almost throughout 

 its extent beneath, the excavation clothed with erect subsquamiform 

 setae. In the female the head, as in complect en i^ 9 , is simple, the 

 three circular foveae forming a large equilateral triangle. These 

 four species, while agreeing generally among themselves, are all 

 very isolated, and the discovery of the male of subtilis and com- 

 plectens may be awaited with interest. In conformity with a gen- 

 eral rule in the present genus, the female is smaller than the male, 

 and has shorter elytra. 



Bythinini. 

 BYTHIIVUS Leach. 



The presence or absence of small raised knobs on the under sur- 

 face of the second palpal joint is not a generic character in this 

 group of species, as these minute tuberosities may be traced more 

 or less readily in nearly every representative ; in our own cari- 

 natus they are extremely feeble, but in tychoides Brend. ( Tyclius 

 hythinioides Br. olim) they are very distinct. In fact Machserodes 

 tychoides agrees almost exactly with an example of Bythinvs italicns 

 in my cabinet, and I cannot perceive that there is even a subgeneric 

 difference in any direction. 



Pselaptrichus is extremely closely allied to Bythinus, differing 

 only in the longer abdomen and more narrowed and produced 

 frontal tubercle, but in view of the variation exhibited in the latter 

 respect by the numerous species of Bythinus, this cannot be con- 

 sidered of very decisive value. The more elongate apparent first 

 dorsal segment is the only really important differential character 

 possessed by Pselaptrichus tuherculipalj^v s Brend., but there can 

 be but little doubt that this alone is sufficient to establish its 

 validity. 



Bythinus is extremel}^ poorly represented in America, but in 

 Europe appears to be the most important element of the family. 



CYLINDRARCTUS Scbaufnss. 



The more elongate third palpal joint, mentioned by Schaufuss 

 and Raffray as a distinguishing feature of this genus, is, it seems 



