184 Mr. D. ShtW^s Contributions to the 



female, tlic apical set^mcnt lias a lateral style on each side, 

 and two more sk-nder ones between them. 



A sinf^le sjiecimen was found by Mr. Bates, but it bears 

 no special indication of locality. 



Diociius. 



This genus consists of seven described species, found in 

 ■widely separated parts of the world, and I now add four 

 new species from the Amazons ; these call for no special 

 remark, as they appear to be extremely closely allied to 

 one another. 



The geniis is one of considerable importance, notwith- 

 standing the insignificant and unattractive appearance of 

 the species which compose it. Some years ago, I examined 

 it, and came to the conclusion that it could not be satis- 

 factorily classed with the Xantholinini, with which it is 

 usually associated. On glancing at some of its points of 

 structure again, I am inclined, however, to suspect that it 

 may prove to be one of the earliest and least specialized 

 forms of the Xantholinini, and that a careful study of its 

 peculiarities may throw considerable light on the natui-e 

 of the modifications distinctive of that group, as well as 

 suggest the species of the Staphylinini, Avith which the 

 Xantholinini are most directly connected. 



1. Diochus longicornis, n. sp. Obscure rufo-testaceus, 

 nitidus, capite elytrisque circa scutellum infuscatis. 

 Long. Corp. 2 lin. 



At once distinguished from D.Jiavicans by the much 

 longer antenna?. These are slender and reach not quite 

 to the extremity of the thorax ; they are of a yellow 

 colour ; 3rd joint is long and slender, longer than the 2nd ; 

 from 4 — 10 each is a little shorter than its predecessor, 

 even the lOtli considerably longer than broad. Head 

 pitchy-red, slightly narrower thai.i the thorax, very little 

 narrow^ed in front, the front part indistinctly ]Hinctured, 

 the punctures })laced in irregular lines. Thorax a little 

 narrower than the elytra, longer than broad, very slightly 

 narrowed in front, dusky reddish-yellow, with four punc- 

 tures near one another on the middle, behind; in front of 

 these with two others farther apart, and with four or five 

 others on each side. Elytra hardly so long as the thorax, 

 yellow, darker about the scutellum, sjiaringly and very 



