DJABEOTICA. 553 



to indicate by testaceous spots those places where in the normal form the ground- 

 colour interrupts the black portion. 



116. Diabrotica allardi. 



Testaceous, the head black; thorax transverse, without depressions; elytra testaceous, finely punctured, a 

 broad transverse band at the base, a much narrower band below the middle, and a still smaller one near 

 the apex, black. 



Length 2f lines. 



Head impunctate, black, the frontal tubercles very narrow ; the clypeus perfectly straight in front, and with a 

 central ridge; labrum flavous; antennae nearly as long as the body, fuscous, the sixth, seventh, and 

 eighth joints whitish, the third joint three times as long as the second ; thorax transverse, the sides nearly 

 straight, the anterior angles obliquely shaped and somewhat produced outwardly, the surface impunctate, 

 without foveae, but with a short oblique groove near the posterior angles ; scutellum testaceous ; elytra 

 finely and closely punctured, with traces of longitudinal grooves, a broad transverse band at the base 

 extending to the first third of their length, a narrower band below the middle and a still narrower one 

 near the apex, black ; underside testaceous, the tibiae and tarsi fuscous. 



Hah. Panama, Bugaba, Pena Blanca {Champion). 



D. allardi possesses all the structural characters of the genus ; but is distinguished 

 from most of the species yet referred to it by its rather transversely-shaped thorax. 

 The first elytral band is narrower at the suture than at the sides, and does not quite 

 extend to the basal margin, where a narrow stripe of the ground-colour remains, and 

 its posterior margin is obliquely cut ; the second band is of half the width of the first, 

 and is slightly rounded and narrowed at the suture ; and the third band is placed near 

 the apex, and is very narrow and slightly curved downwards at the outer ends ; neither 

 of the bands extend quite to the lateral margin. 



117. Diabrotica sex-plagiata. (Tab. XXXI. figg. 14 ; 15, var.) 



Diabrotica sexplagiata, Jac. P. Z. S. 1878, p. 151 1 . 



Var. Thorax without longitudinal lateral stripes ; elytra yellowish-white, margined with black. 



Hob. Mexico, Teapa, Tuxtla (Salle), Jalapa, Tapachula in Chiapas (Hoge); British 

 Honduras, P. Hondo, Belize (Blancaneaux) ; Guatemala, Zapote, San Geronimo, 

 Chacoj (Champion); Nicaragua, Chontales (Janson); Panama 1 , Bugaba, Volcan de 

 Chiriqui, David (Champion). — Colombia (coll. Baly). 



In the type the whitish colour of the elytra is divided by narrow transverse black 

 bands into six spots or patches (three on each) ; these spots or patches become more or 

 less confluent in the varieties till the dividing dark transverse bands disappear altogether, 

 and produce a uniformly coloured form in which the elytra are simply margined with 

 black ; the elytra themselves are closely rugose-punctate. The four anterior femora 

 are generally striped with black above, and the apex of the posterior femora, and the 

 posterior tibiae entirely, of that colour. The locality " Peru " given by me 1 refers to a 

 closely allied but distinct species, as I found upon a closer examination. Many examples. 



We figure a typical specimen from Belize, and a variety from Tapachula. 

 biol. centr.-amer., Coleopt., Vol. VI. Pt. 1, October 1887. 4 b 



