g 



522 PHYTOPHAGA. 



45. Diabrotica nigro-signata. (Tab. XXX. fig. 10.) 



Flavous, the antennae and tibiae black ; thorax bifoveolate ; elytra scarcely visibly punctured, testaceous, a 

 spot at the base, a short longitudinal stripe at the shoulders, and a triangular spot near the apex of 

 each, black. 



Length 2 lines. 



Head impunetate, fulvous, the lower part flavous ; the frontal tubercles indistinct, narrowly transverse • 

 antenna? nearly as long as the body, entirely black, the second and third joints short, equal, the fourth 

 joint very long ; thorax subquadrate, narrowed at the base, the surface with two broad and rather deep 

 depressions and an obsolete groove near the anterior margin, the disc shining, fulvous, impunetate ; 

 scutellum flavous ; elytra rather flattened and parallel, only very finely punctured near the suture, with 

 an elongate spot near the scutellum, a longer stripe (pointed at its upper end) extending from the 

 shoulders nearly to the middle, and a subtriangular spot near the apex of each, black, the markings 

 smooth ; the underside and legs flavous, the tibiae and tarsi black. 



Hab. Guatemala, San Geronimo, San Isidro {Champion). 



D. nigro-signata differs entirely from any of the preceding species by the elytra bein 

 scarcely visibly punctured and by the markings being differently placed. 

 An example from San Geronimo is figured. 



46. Diabrotica trifurcata. (Tab. XXX. fig. 4.) 



Head, the intermediate joints of the antennae, the breast, tibiae, and tarsi, black ; thorax rufous, with three 

 depressions ; elytra testaceous, a transverse band at the base split into three branches, and an undivided 

 one near the apex, violaceous-blue. 



Var. Legs entirely fulvous. 



Length 3 lines. 



Head impunetate, bluish-black ; antennae two thirds the length of the body, the third joint nearly twice the 

 length of the second, the three or four basal and the three apical joints fulvous, the others black ; thorax 

 slightly broader than long, reddish-fulvous, shining, the disc with an obscure basal and two deep lateral 

 depressions, the surface impunetate ; elytra closely punctured, the interstices somewhat rugose, with the 

 blue basal band placed across the basal margin and divided into three branches (of which the lateral are 

 the longest and placed at the shoulders, the intermediate one occupying the sutural margin anteriorly) 

 and the transverse narrow band below the middle slightly curved and narrower towards the suture. 



Hab. Nicakagua, Chontales (Janson, Belt); Costa Kica, Volcan de Irazu (Sogers); 

 Panama, Volcan de Chiriqui (Champion). 



The principal distinguishing characters of this species are the subapical transverse 

 blue band of the elytra and the reddish-fulvous thorax ; and, also, the connection at the 

 base of the three anterior elytral stripes, these stripes being pointed and in some 

 specimens showing inclinations of again uniting at their lower ends — thus indicating a 

 similar pattern to that found in D. adelpha and allied species. There are several 

 forms before me which show slight differences in the thickness of the elytral stripes 

 and also in the colour of the legs ; but I am unable to say with certainty whether these 

 must be looked upon as varieties or not. 



We figure a specimen from the Volcan de Chiriqui. 



