EUCNEMID^E.— MELASIS. 213 



23. Antennae with joints 2 and 3 very short, together not as long as 



the fourth Entomophthalmus. 



Antennae with joints 2 and 3 together much longer than the 



fourth Microrhagus. 



24. Last ventral segment obtuse at the tip 25. 



Last ventral segment acutely prolonged at the tip 27. 



25. First joint of the hind tarsi as long as the following joints together. Adelothyreus. 

 First joint of the hind tarsi notably shorter than the following 



joints together 26. 



26. Outer carina of the propleural depression entire Farsus. s 



Outer carina of the propleural depression extending only halfway 



to the base Arrhipis. 



27. Outer carina of the propleural depression entirely absent . . . Adelorhagus. 



28. Metasternal episterna moderately wide, parallel-sided .... Pterotarsus. 

 Metasternal episterna narrow, narrowed in front Thylacosternus . 



CEKOPHYTUM. 



Cerophytum, Latreille, Gen. Crust, et Ins. iv. p. 375 (1809) ; de Bonvouloir, Mon. des Eucnemides, 



p. 78. 

 Chorea, Haldeman, Proc. Acad. Phil. iii. p. 150. 



This genus at present contains but five species ; two are from temperate North 

 America and one each from Europe, Mexico, and South America. It is an aberrant 

 member of the family, exhibiting tendencies in the direction of the Dascyllidee, although 

 possessing in a moderate degree the saltatorial power of the Elateridse. 



1. Cerophytum fuscicorne. 



Cerophytum fuscicorne, de Bonv. Mon. p. 84, t. 4. fig. 3 \ 



Hab. Mexico x ; Panama, Volcan de Chiriqui (Champion). — Colombia, Cartagena 1 . 



One male specimen of the typical form, piceous-black, in our series. The antennae 

 have a structure similar to that of the males of the other species. 



MELASIS. 



Melasis, Olivier, Ent. ii. no. 30 (1790) j de Bonvouloir, Mon. des Eucnemides, p. 88. 



This genus, with the following, constitutes a subdivision of the family in which the 

 prosternal sutures are parallel to each other and to the lateral margin of the thorax, 

 a character not commonly observed in the true serricorn series. 



l. Melasis rufipalpis. 



Melasis rufipalpis, Chevr. Col. Mex. cent. ii. fasc. 8, no. 193 1 ; de Bonv. Mon. p. 94, t. 4. fig. 6\ 

 Hab. Mexico 2 , Las Vigas 1 ; Guatemala, Coban in Vera Paz (Conradt). 



