ZYGOGEAMMA. 213 



nearly to the base of the elytra ; in the present insect this band is distinctly widened at 

 a little distance below the base, while the rest of the disk below the middle is occupied 

 by numerous small spots, which are sometimes more or less confluent. In general 

 shape the species is larger, more convex, and broader ; and the thorax is transverse, and 

 as wide as the base of the elytra, which is not the case in Z. piceicollis. I may further 

 add that in Z. lemur there are two (and often three) confluent spots at the shoulder, 

 generally connected with the suture at the base. 



9. Zygogramma opifera. (Tab. XII. figg. 10, 11.) 



Calligrapha opifera, Stal, Diagn. I860, p. 460; Monogr. Chrys. Amer. p. 246 \ 

 Hab. Mexico 1 , Puebla, Tepanistlahuca [Salle). 



Both typical specimens, from Mr. Baly's and Deyrolle's collection, I have for 

 examination, as well as two specimens from Puebla. The most characteristic design of 

 the elytra is a broad longitudinal curved band from the shoulder to the middle, which 

 is either so wide as to occupy nearly the entire anterior portion (with the exception of 

 the sides, which are always spotless but have a narrow stripe from the middle to the 

 apex at the extreme lateral margin), or is very narrow, but of the same shape, and 

 frequently connected with the broad sutural band before and behind the middle. In 

 some specimens this band predominates to such an extent as to leave only three small 

 testaceous spots parallel with the suture — one at the base, the second before, and the 

 third behind the middle. Between this variety and the one in which the vitta is 

 narrow there are intermediate degrees ; but two minute spots near the side, one at the 

 middle, the other near the apex, seem to be constantly present. 



10. Zygogramma bigenera. (Tab. XI. fig. 22.) 



Calligrapha bigenera, Stal, Diagn. 1859, p. 322; Monogr. Chrys. Amer. p. 254 \ 



Hab. Mexico \ Toxpam, Cordova, Playa Vicente, Orizaba (Salle), Oaxaca (Hoge) ; 

 Guatemala, Chacoj, Panima, Tamahu, Teleman, Purula (Champion); Nicaeagua, Chon- 

 tales (Janson, Belt) ; Costa Rica, Cache (Rogers). 



This species seems to have less propensity to vary than many others, the numerous 

 specimens which are before me from the above localities scarcely varying in their elytral 

 designs. The insect is of short and convex form, with almost white or slightly yellowish- 

 white elytra, with the dark markings brownish or greenish seneous ; the sutural band is 

 always connected before the middle with the shoulder-stripe by a thin branch which 

 joins the latter, and below which four spots are generally placed parallel and at some 

 distance from the lateral margin (the second of which is the largest, the others being 

 very small); there is also in nearly all specimens a more or less distinct spot at the 

 middle of the last punctured stria near the lateral margin. Thorax and legs are often 

 obscure rufous or piceous. A specimen from Nicaragua is figured. 



