138 Mr. G. J. Arrow on some 



conclusions expressed in the above work, I have thought it 

 best to prepare a short supplementary paper. 1 have omitted 

 certain species which it seemed could be more adequately 

 described when further specimens have been received. 



The specimens ascribed by Bates to Cydocephala mutata 

 represent four distinct akiiougli closely related species, those 

 from Yucatan only being the true C. mutata [C. frontalis^ 

 Burn).). Two of the Costa-Kican specimens belong to 

 C. sororia, Bates, while the remainder of the extra-Mexican 

 individuals constitute a new species and those from the 

 northern part of Mexico another. 



Cydocephala viarginicolUsj sp. n. 



Tcstacea, cylindrica, immaculata, tarsis suturaque tenuissime rufes- 

 ceiitibus; capite ruio-fusco, vertice nigro, clypeo lato, vix producto, 

 rugoso ( J subtilissime), vertice crebre punctato; prothorace sat 

 hito, nitido, leviter punctato, ubique linea incisa marginato, 

 lateribus fortiter arcuatis, angulis anticis acutis, posticis curvatis ; 

 scutello paulo punctato, signa Y-formi vage impresso ; elytris 

 grosse lineato-punctatis, $ lateribus post medium dilatatis ; 

 pygidio, S fere opaco, subtilissime punctato, $ subuitido, dis- 

 tincte insequaUter punctato. 



Long. 16-18 mm. 



JTdb. Mexico, Cordova, Playa Vicente. 



This species and C. mutata, G. & H., are extremely close 

 to one another. The true C. mutata, however, seems to be 

 confined to Yucatan, from which ►State it was described. 

 ►Seven specimens from there in our collection have enabled 

 me to separate the two forms, being entirely devoid of a 

 marginal line at the posterior border of the pronotum, 

 whereas in the new species it is very distinct. The only 

 other differences which I am able to find are the absence in 

 C. mutata of the Y-shaped depression on the scutellum, which 

 is more or less visible in the northern form, and the absence 

 c£ punctures on the posterior part of the head. 



Cydocephala Icevicauda, sp. n. 



Cylindrica, pallide testacea, elytris pellucidis ; capite pygidioque 

 ' rufo-fuscis, vertice nigro ; abdomine, tibiis tarsisque rufescentibus : 

 clypeo lato, vix producto, subtiliter rugoso, vertice mediocriter 

 punctate ; prothorace polito, parce et miuute punctato, postice 

 immarginato, lateribus valde arcuatis, angulis anticis subacutis, 

 posticis curvatis ; scutello vix punctato ; elytris laevissime hneato- 

 ])iinctatis, $ lateribus post medium dilatatis ; pygidio politissimo. 



Long. 15-17 ram. 



