16 HEMIPTERA-HOMOPTERA. 
*Gibbose,” of the genus Membracis [v. Rev. Ent. Silb. iii. p. 229 (1835)], and he 
concludes his remarks regarding them with the following observation, which applies 
with equal force to many other of the genera and species of the Membracide :—“ Species 
divisionis ultime ita ab illis primee divisionis recedunt, ut proprii generis typos credas, 
sed in characteribus gravioris momenti conveniunt, et omnes quatuor divisiones formis 
intermediis inter se coherent. Stethidii diversitates semper caute queras, ne tot genera 
quot species exstant condas!” 
Owing to the close resemblance that the species of Bolbonota bear to one another 
and the meagreness of the descriptions of many of the types, the difficulty of deter- 
mining them rightly is very greatly increased, and very little is really known about the 
genus as a whole, which appears to contain a considerable number of species from 
Central and Tropical South America. ‘They are, as a rule, very scantily represented 
in collections: in our collection there are large series of two or three species, which 
appear to vary considerably in size, colour of elytra, and (to a certain extent) in 
sculpture; and it is most probable that when the group is more worked and further 
material collected, several of the species already described will be found to be 
identical. 
Dr. Goding (Canad. Ent. xxv. p. 55) separates the genus into two subgenera as 
follows :— 
Posterior process of pronotum behind middle furnished with a high 
transverse tubercle or spine, more or less compressed antero-poste- 
riorly ; anterior part strongly and gradually elevated up to middle. Tubercunota, Goding. 
Posterior process from apex, seen from side, depressed; in front of 
depressed part dorsum straight or lightly bisinuate . . . . . Bolbonota, A. &S. 
This distinction makes a good division in most cases, although certain species appear 
to be transitional ; in examining the dorsal ridge the insect must be held perfectly 
upright and viewed exactly from the side. 
Through the kindness of Herr Handlirsch 1 have been enabled to examine typical 
specimens of several of Signoret’s species in the Vienna Museum (referred to by 
Fairmaire}, which has been a great help towards determining the new species; but 
there are several of the species which have been described that I have not been able to 
see, and it is impossible to know what they are from the descriptions. A short mono- 
graph of the genus is much to be wished for, but no satisfactory one can be drawn up 
without an examination of all the types hitherto described and of larger series of the 
species than are at present available. . 
So far as I know, only one species has hitherto been recorded from any locality 
further north than Bogota. This is B. aurosericea, recently described by myself 
from a specimen in the Vienna Museum labelled “North America” (Trans. Ent. Soc. 
Lond. 1894, p. 417). 
