CUCUJID.E 113 



stituting the subfamily Passandrinae; they are widely isolated among 

 themselves and annectent forms are apparently unknown. In fact 

 the generic type is so paramount, that the species forming the 

 genera are subject to exceedingly limited diversification and, while 

 these species seem to be as real as in other genera, they present 

 so marked a uniformity to external view as to appear arbitrary or 

 artificial until studied carefully in series. As a group of genera the 

 Passandrids are as unlike the remainder of the Cucujidae, as Paran- 

 dra is unlike the other Cerambycids, or perhaps more so, and 

 personally I am almost in favor of considering them a distinct 

 family of Coleoptera. We very often perceive a diffidence on the 

 part of systematists toward the idea of increasing family groups, 

 but I cannot understand why it would not be more satisfactory to 

 tabulate a large number of family groups in such a series as the 

 Clavicornia, than to attempt to assemble recognized subfamilies 

 into inharmonious series called families. Omitting Hemipeplus, 

 we- might propose at least four families from the Cucujidse for 

 instance Passandridae, Laemophlreidae, Silvanidse and Hypoco- 

 pridae. One remarkable feature of the Passandrinae, of peculiar 

 persistence and uniformity and betraying an alliance with some 

 subcortical groups of Tenebrionidae, is the deep transverse sulcus 

 of the last ventral segment, which is similar in the sexes and alto- 

 gether obscure as to origin and meaning. 



In Passandra, the species, following the general rule in the sub- 

 family, are mutually very similar in appearance, but the following 

 seems to be different from any hitherto described: 



*Passandra mexicana n. sp. Form oblong, subparallel, depressed, dark 

 castaneous in color throughout, excepting a broad black vitta along the 

 elytral suture from base to about apical fifth or sixth; integuments highly 

 polished, without fine ground sculpture and with scarcely any trace of 

 punctuation; head very nearly as wide as the prothorax, with the usual 

 two broad longitudinal impressions and the median depression at apex, 

 the long sulcus above the eyes very abrupt, deep and with its bottom 

 alutaceous; mandibles rather small, thick; eyes small, convex, moderately 

 coarsely faceted; antennae filiform, stout, polished, deep black, extending 

 to apical third of the elytra, each joint as usual broadly constricted post- 

 medially, the last joint twice as long as wide, strongly and evenly arcuate 

 in external, and broadly sinuate in internal, outline, the apical edge to 

 behind the middle abruptly beveled, opaque and sensitive; prothorax 

 wider than long, of the usual form, the sublateral stria not attaining the 

 apex and ending at basal third; surface between the stria and the sides 

 T. L. Casey, Mem. Col. VII, Nov. 1916. 



