538 PHYTOPHAGA. 



81. Diabrotica medio-vittata. 



Diabrotica mediovittata, Baly, Journ. Linn. Soc, Zool. xix. p. 237 \ 



Hab. Honduras {Salle); Nicaragua, Chontales (Janson); Panama, Bugaba, Volcan 

 de Chiriqui (Champion). — Eastern Colombia *. 



The type of D. medio-vittata, kindly lent to me by its describer, agrees in all respects 

 with specimens from Nicaragua and also with others from the State of Panama. There 

 are, however, other examples before me undoubtedly belonging to D. medio-vittata 

 which differ in the sculpture of the elytra, a character perhaps peculiar to the female 

 sex ; in these specimens each elytron has about six thin, raised, slightly curved costae 

 which disappear entirely before the apex. In the normal form the elytra are simply 

 punctured, but more strongly so towards the sides ; both forms were obtained at the 

 same time and place and differ in no other way. D. medio-vittata has black elytra, a 

 narrow flavous outer margin, interrupted behind, and a discoidal subsutural vitta which 

 does not extend to the apex but is slightly curved in shape and widened at its posterior 

 portion. The antennge are black, with the two penultimate joints obscure flavous ; and 

 the femora generally have a piceous stripe on their upper edge. D. similata, Baly, 

 seems to me to be identical with D. medio-vittata, according to the description, and to 

 represent the form in which the elytra are costate ; the variety of the former with less 

 distinctly costate elytra noticed by Mr. Baly showing the intermediate stage. 



82. Diabrotica horni. 



Ovate, dilated posteriorly, black ; antennae long and slender, black, the apical three joints obscure flavous ; 

 thorax fulvous or flavous, deeply bifoveolate ; elytra with a subsutural and lateral flavous vitta, strongly 

 punctured at the sides, more finely on the disc ; femora flavous at the base, 

 c? . Lower part of the face flavous ; antennae as long as the body. 

 2 . Head entirely black ; antennae shorter. 



Var. Antennae, the intermediate joints excepted, and legs fulvous. 

 Length l|-2 lines. 



Hab. Mexico, Playa Vicente, Tuxtla (SalU), Jalapa, Teapa, Tapachula (Edge); 

 British Honduras, E. Hondo (Blancaneaux) ; Guatemala, El Tumbador, El Eeposo, 

 Cerro Zunil, Zapote (Champion) ; Nicaragua, Chontales (Janson). 



Closely allied in shape and coloration to D. separata, Baly, but differing in the much 

 longer and thinner antennae, these organs in the male extending to the end of the elytra. 

 D. horni may, however, be principally separated from its allies by the elytra having no 

 costae, and consequently the flavous subsutural band, although as broad as in L. sepa- 

 rata, is not raised and smooth but flattened like the rest of the disc and punctured ; 

 the lateral portion of the elytra is coarsely punctured, the interstices being somewhat 

 rugose with traces of narrow longitudinal cost*. In several specimens the sixth, seventh, 

 and eighth joints of the antennae are black, the other joints and the legs fulvous ; other 

 differences I am not able to find ; I therefore treat these as a variety of D. horni. 



