54 ORTHOPTEROUS INSECTS BELONGING TO 
a conical plate hollowed out above, and more elongated and entire 
in the male, whilst it is longitudinally divided in the female; the 
9th ventral segment in both sexes being represented by the two 
small horny triangular plates, behind or beneath the small conical 
appendage common to Orthopterous insects. It is in the variation 
of form of these several pieces that the sexes are distinguished.* 
The general colour of the insect is fulvous-yellow, considerably 
spotted and marked with black and dark brown, especially on the 
thighs and back of the thoracic segments. 
No species of this genus has hitherto been described as inhabiting 
any other part of South America than Brazil. The present species, 
therefore, presents us with an instance of a wider geographical 
range, being a native of the western portion of South America, 
whence it was brought, I believe, by Mr. Cuming: it is from this cir- 
cumstance that I have given to it the specific name employed above. 
Proscopia is one of those singular forms which exhibit a great 
resemblance to the species of a family different from that to 
which they in reality belong. Thus, we have here the long slender 
cylindric body of Bacteria amongst the Phasmidz, as well as their 
apterous condition. M. Brullé also mentions two other characters 
possessed by these insects analogous to those of the Phasmide, 
namely, the plate terminating the abdomen of the males, and the 
compressed and angulated palpi. They appear to represent the 
old world genus Truxalis, in South America, and are evidently 
brought into relation with the more typical Locusts by that genus, 
and especially by the genus Mastaxf, (illustrated in the first volume 
of this work, pl. 26), and by the Astroma chloropterum of Charpen- 
tier}, a most interesting insect, also from Chili, (allied to Proscopia, 
and also to Tetrix Latr.,) which is described as destitute of all 
traces of the wing-covers, but having two small greenish wings 
arising from the first segment of the body (after the prothorax). 
* I presume that M. Brullé’s first ventral arc in the males is the hind part of the meta- 
sternum, separated from the anterior part by an impressed line, which, however, exists less 
distinctly in the females; and that his 9th ventrai segment in the male is the undivided conical 
eighth ventral arc. 5 
+ Germar’s Zeitsch. f. d. Ent. 3, 305. 
$ I take this opportunity of describing a new species of Mastax, recently forwarded to me 
from Assam, by Mr. Robinson, by way of supplement to the Memoir on this genus in the 
first volume of this work. 
Mastax arrinis. W. Fusca, facie et lateribus fulvescentibus, capite erecto vertice ad apicem 
truncato subbifido, prothorace carina elevataacuta, abdomine ¢ adapicem valde inflato, tegmi- 
nibus fuscis guttis duabu hyalinis, alis fulvis margine tenui fusco. M. guttate valde aftinis 
sed multo major. Long. corp. lin. 10. Expans. tegmin. lin. 22. 
Habitat. Assam, Ind. Or. In Mus. nostr. amicissime communic. D.Robinson. 
