MelolontJnd and Eatelid Cohoptera. 305 



species upon wliich it is founded^ a name is not entitled to 

 recognition so long as it is unaccompanied by a description to 

 afford evidence as to its identity. For this purpose, o£ course, 

 description of the typical species, or even a statement that 

 the genus is based upon an actual type specimen, must be 

 admitted as sufficient. 



I theiefore consider that eucalifpti^ Boisd., and its con- 

 geners should properly be called Stethaspi's, and for the New 

 Zealand insect {suturalis, Fabr.) I propose the new name 

 Chlorochiton. The genus has been fully characterized by 

 Lacordaire, but I have given its essential characters in the 

 table which follows, in order to compare it with its nearest 

 allies, with which it was not associated by that entomologist. 

 One of these has hitherto been wrongly placed with the 

 Rutelidse; this is Modialis prasinellay Fairm., a Chilian 

 insect, whose closest affinity seems to me to be with Phytoloema, 

 another Chilian genus belonging to the Heteronycides of 

 Lacordaire. 



Tiie latter genus and Chlorochiton {Stethaspis, Lacord.) were 

 assigned to different groups by Lacordaire on account of the 

 produced metasternum of the latter. Later knowledge has 

 shown that this feature is exceedingly inconstant and liable 

 to be misleading as a basis of classification, and its occurrence 

 in Modialis seems to me to necessitate the fusion of the 

 groups 8tethaspides and Heteronycides. With the exception 

 of Phytolcema and one or two other small genera occurring 

 on the Pacific coast of South America, all the insects placed 

 in both divisions belong to the Australian Region, so that this 

 course is supported by their geographical distribution. 



The following table shows the differential characters of 

 these hitherto scattered genera which I am proposing to bring 

 together. Although all highly peculiar forms, and differing 

 in important particulars, I consider that tliey have closer 

 relationships among themselves than with any other genera 

 known to me. They all agree in a superficially Ruteloid 

 appearance, in their prominent front coxse, distinct and 

 emarginate labrum, and ligula fused with the mentum. 



Junction of mentum and ligula straight ; claws simple. 



Antennae 8-jointed; club 3-jointed Chlorochiton (New Zeal.). 



Antennie 9-jointed ; club 5- or 6-jointed . . Stethaspis (Australia). 

 Junction of mentum and ligula augulate ; claws toothed. 

 AntennfB 8-jointed; club 4-jointed (J); 



metasternum not produced Phijtolcema (Chili). 



Antennas 9-jointed; club 3-jointed; meta- 

 sternum produced Modialis (Chili). 



Stethaftp)is [Xyhnychm^ Lacord.) was placed with the true 



