514 PHTTOPHAGA. 



27. Diabrotica nummularis. (Tab. XXIX. fig. 6.) 



Diabrotica nummularis, Harold, Mittheil. Munch, ent. Ver. p. 110 (1877) 1 . 



Hal. Mexico \ Ventanas, Milpas (Forrer), Juquila, Yolotepec, Cuernavaca, Cordova, 

 Vera Cruz (Salle), Jalapa, Chilpancingo, Colima city, Acapulco, Tapachula (Hoge) ; 

 Costa Eica (Van Patten), Cache (Rogers); Panama, Bugaba, Volcan de Chiriqui 

 (Champion). 



It is not easy to come to a definite opinion in regard to this species and several 

 of its closely-allied congeners ; and after a great deal of careful examination I can only 

 form the conclusion that at least two forms of D. nummularis must be distinguished, 

 if indeed all the specimens before me are to be referred to that species. In the typical 

 form the antennae and legs are entirely fulvous, the head is black, and the elytra have 

 a broad metallic blue ring at the base and an equally broad semilunate band below the 

 middle ; in the second form the elytral markings (although similar in shape) are much 

 thinner and the head is either entirely or partially fulvous, but specimens with a black 

 head also occur. In all, the thorax is of a reddish-fulvous colour, rather convex, and 

 with two small foveas. It is impossible to separate the two forms on account of the 

 many intermediate degrees of colour and elytral pattern ; but the constant characters 

 peculiar to D. nummularis seem to be the entirely fulvous antennae and legs, in con- 

 nection with the reddish, convex, and finely bifoveolate thorax. Some examples 

 exactly resemble in the closed elytral rings D. hiannularis ; but as the colour of the 

 antennae and the shape of the thorax agree with D. nummularis I look upon them as 

 varieties of that species. The specimen figured, from Ventanas, belongs to the form 

 with thin elytral pattern. 



28. Diabrotica delineata. (Tab. XXIX. fig. 10.) 



Pale testaceous, the breast and the sixth, seventh, and eighth joints of the antenna? black ; thorax bifoveolate; 



elytra closely and distinctly punctured, a thin ring-shaped mark at the base and another half-ring below 



the middle, violaceous-blue. 

 Length 3 lines. 



Hob. Mexico, Cordova, Tuxtla (Salle), Jalapa (Edge) ; Beitish Honduras, E. Hondo 

 (Blancaneaux) ; Guatemala, Volcan de Atitlan (Champion). 



I separate D. delineata from D. hiannularis on account of the flavous head the 

 colour of the antennae (in which the sixth to the eighth joints only are black), and the 

 generally paler colour. The elytra are more opaque, closely punctured, and with traces 

 of longitudinal depressions ; the ring-shaped marks are very thin, the posterior one being 

 open behind and forming an angulate half-crescent. As these differences are constant 

 in the nine specimens before me I must look upon them as of specific value. We 

 figure an example from Cordova. 



