324 PHYTOPHAGA. 



San Geronimo, Zapote, Capetillo (Champion)-, Costa Eica, Cache (Sogers) ; Panama, 

 Volcan de Chiriqui, Bugaba (Champion). 



More than a hundred specimens from the above localities, which, in regard to colour 

 and size, vary in a most extraordinary manner, have brought me to the conclusion that 

 they represent but one species, as I cannot find any structural character for their 

 separation. The colour of the upper parts, as given above, represents only those of the 

 more immediate contrast ; between these a great number of other varieties and interme- 

 diate degrees, too numerous to mention, are before me. The head and thorax vary from 

 red to black, or spotted with either colour, and the same applies to the elytra, of which 

 some specimens have the latter black with a yellow margin or yellow with a black 

 margin, spotted or unspotted; in all the head is impunctate, the frontal tubercles 

 flattened and separated by a central groove, but not behind ; the antennae (as variable 

 in colour as the other parts) are slender, and have the third and fourth joints equal; 

 the thorax is scarcely visibly, the elytra more distinctly and very closely punctured. 

 This species is generally of a semiflattened, posteriorly widened shape, but frequently 

 more parallel ; the black specimens often have the head only fulvous, in which colour 

 they resemble greatly 8. frontalis, Fabr. ; but the finely punctured upper surface of the 

 present insect will separate them from the latter species. I am the more certain that 

 all the varieties described here represent but one species, as the greater part of them 

 were obtained at the same locality (Volcan de Chiriqui) and at the same elevation of 

 2500 to 4000 feet. 



5. Systena nigroplagiata. (Tab. XIX. figg. 23, 24.) 



Below black ; head, thorax, antennae, and legs fulvous ; elytra minutely punctured, fulvous, a triangular spot 

 surrounding the scutellum, another small spot near the lateral margin, and a transverse band below the 

 middle black. 



Var. a. Upper part of the head, a spot on the disc of the thorax, and the antennae black. 



Var. b. Testaceous above, the black markings of the elytra reduced to small spots. 



Length 2|-3 lines. 



Hab. Mexico, Guanajuato, Cuernavaca, Juquila (coll. Salle), Milpas (Forrer), Jalapa 

 (Edge). 



I separate this species on account of the different pattern of its elytra, which 

 have a triangular-shaped spot at the base surrounding the scutellum, and a very 

 small spot between the basal and postmedian band on the lateral margin; this 

 small spot is always present in this species, while in the variety b the band and other 

 markings are represented by small spots, placed, however, in the same way as in the 

 type. Of both forms I have sufficient material for comparison, but I have seen 

 nothing intermediate. The punctuation of this species is rather more finely impressed, 

 if anything, than in S. variabilis; the shape and other particulars are the same. 



