Classification of the Coleopterous fanuly Endoniychidae. 35 



P. tonkinensis Arrow (recently described in Ann. Mag. 

 Nat. Hist.), with less conspicuously flattened margins. 



In the male the 9th joint of the antenna is larger than 

 the loth, but scarcely as large as the 11th. 



Genus Danae. 



The genera Danae and Saula consist of very numerous 

 and extremely similar minute species, which have so far 

 received no careful study. In his monograph Gerstaecker 

 described two species belonging to the first genus under 

 the name of Oediarthrus, and stated that the enlargement 

 of the 9th joint of the antenna was common to both sexes. 

 This is a mistake which has led astray those who have 

 followed him and has not been corrected in the recent 

 catalogue. Weise has recognised the sexual character of 

 the remarkable antennal structure, but has added to the 

 existing difficulties by giving new names to female speci- 

 mens. The 9th antennal joint is found in all degrees of 

 development in the males of diiierent species and is of 

 normal form in the females, so that it is useless as a generic 

 character, and the many species I have been able to bring 

 together show that nothing remains by which it is possible 

 to separate generically Danae, Oediarthrus, Rhabduchus 

 and Coniopoda. All these are distinguished from Saida 

 by the broadly margined prothorax and transversely 

 elliptical scutellum. The genus Heliobletus, which Cziki 

 has amalgamated with Saula, is intermediate between 

 the latter and Danae, being (Hke Saula) without a wide 

 prothoracic margin but, like Danae, having the scutellum 

 transverse and rounded, while the antennae have also the 

 9tli joint enlarged in the nude, which has not hitherto 

 been laiown. 



In addition to this curious feature of the male antenna 

 in these two genera, striking dift'erences may also be found 

 in the legs in the same sex and these afford the best means 

 of distinguishing the species. The females, on the other 

 hand, are so nuich aUke that unless they can be associated 

 without doubt with the other sex they are best left alone. 



As already mentioned, I refer to Danae the North 

 American " Mycetina" testacea Ziegl., which is not very 

 remote from the Japanese D. orientalis Gorh. In these 

 species external sexual diflerences are practically absent. 



Danae rufula Heiche, venusLula Gestro, abdominalis and 



