DIABKOTICA, 511 



base and a similarly-coloured round or oval spot behind the middle ; many specimens 

 have a small yellow spot placed in the middle of the basal band ; and some vary in such 

 a way that one might feel inclined to regard D. pulchella as a variety of D. biannularis 

 in which the rings of the elytra have been filled up. This insect is not uncommon at 

 Chontales. We figure a specimen from Cordova. 



c. Elytra flavous, with fulvous bands and spots. 



21. Diabrotica octo-plagiata. (Tab. XXX. fig. 17.) 



Flavous, the breast obscure piceous ; thorax bifoveolate : elytra closely punctured, flavous, two spots at the 

 base, a transverse band at the middle, and another deeply sinuate one near the apex, dark fulvous. 



Length 2f lines. 



Head impunctate, the frontal tubercles strongly raised ; labrum piceous ; palpi flavous ; antennae two thirds 

 the length of the body in the male, shorter in the female, flavous, the third joint scarcely longer than the 

 second, the fourth not or scarcely longer than the fifth joint; thorax subquadrate, flavous, the disc with 

 two deep depressions, impunctate ; elytra longitudinally grooved on each side below the shoulders (more 

 distinctly so in the male than in the female), with a longitudinal spot at the shoulder, another near the 

 scutellum, a perfectly straight transverse band at the middle, and a similar band (deeply sinuate on its 

 posterior margin) near the apex of each, dark fulvous ; legs flavous. 



Eab. Guatemala [Salle) ; Nicaragua, Chontales (Janson). 



In this insect neither the spots nor the bands touch the margins of the elytra ; the 

 female is of more convex shape and rather larger than the male, and has the punc- 

 tuation of the elytra not so distinct. I have seen but two specimens of this species, 

 which is very distinct by the colour of the bands and the pattern of the elytra. The 

 Guatemalan example is figured. 



d. Elytra flavous, with black or blue more or less ring'shaped anterior and posterior 



markings. 



22. Diabrotica adelpha. (Tab. XXIX. fig. 8.) 



• Diabrotica adelpha, Harold, Coleopt. Hefte, xiii. p. 92 (1875) \ 



Sab. Guatemala \ near the city, Capetillo, Duerias, Zapote, Cerro Zunil (Champion), 

 Yzabal (Salle) ; Nicaragua, Chontales (Janson) ; Costa Rica ( Van Patten), Irazu, Bio 

 Sucio, Volcan de Irazu (Rogers) ; Panama, Bugaba, Volcan de Chiriqui (Champion). 



This and several of the following species are extremely closely allied, their characters 

 of distinction being slight and variable. D. adelpha may be separated by the smooth, 

 not foveolate, thorax ; and by the anterior ring-shaped elytral mark, the posterior 

 margin of which is produced laterally into a short band, which, however, does not 

 extend to the lateral margin : this pattern resembles exactly that of D. gratiosa, but in 

 that species the posterior mark of the elytra is not ring-shaped, but nearly straight or 

 very slightly curved* Von Harold speaks of a variety in which the rings of the elytra 



