ACEOOAEA.— MACH^KOCERA. , 49 



1. Acrocara maculipeimis, Scudder. (Tab. I. figg. l, l a, $ .) 



Acrocara maculipenne, Scudd. Psyche, v. pp. 437, 438 (1890) \ 



Hab. Mexico, Montelovez in Coahuila (coll. Scudder 1 ), Villa Lerdo in Durango 

 (coll. Bruner 1 ). 



The only specimens of this locust before me are two males from Montelovez, found 

 on September 20th, and a single female from Villa Lerdo, found in November ; it is 

 natural to surmise, therefore, that it is either quite rare or else restricted in its 

 distribution to peculiar localities or certain food-plants. The female referred to above 

 was captured by the present writer ; so far as my memory serves me, it was found upon 

 a low thorny herb with greyish leaves growing in alkali soil at the foot of a steep 

 rocky slope. Although a careful search was made at the time, no additional specimens 

 could be found. 



MACH^ROCERA, Saussure. 

 Machcerocera, Saussure, Rev. et Mag. Zool. xi. p. 391 (1859). 



The insects comprising this genus are confined to Mexico and the northern portions 

 of Central America, where they seem to be generally distributed in the more humid 

 districts. Their general colour is dusky, of some shade of brown, and, in certain forms, 

 occasionally marked with lighter tints along the dorsum and on the hind femora. The 

 wings are blue, becoming more or less heavily infuscated on the apical half or two- 

 thirds. The various species differ one from the other chiefly in size and form, and, as 

 a rule, occupy different sections of the country. The annexed table will aid in 

 distinguishing them. 



Table for separating the Species of Machserocera. 



A 1 . Hind wings with the dusky portion dense and quite uniform, occupy- 

 ing the greater part of the apical two-thirds, and in some instances, 

 perhaps, quite three-fourths. 

 b l . Hind tibiae decidedly blue or bluish ; the hind femora marked with 

 three yellow bands. Dorsum usually provided with a longitudinal 

 pale stripe. [Occurs near the Gulf Coast from Tampico to Yucatan 



— a slender, rather long- winged insect.] 1. mexicana, Sauss. 



b\ Hind tibiae more or less rufous, or fuscous, but sometimes with a 



bluish tinge ; the hind femora less prominently banded. Dorsum 



generally without the pale longitudinal stripe. 



c 1 . Rather slender. General colour very dark brown, the tegmina 



usually not conspicuously light-coloured on the dorsal field. 



[Mexico, Guatemala, and Honduras.] 2. obscura, sp. n. 



c 2 . More robust. General colour ferruginous-brown, the dorsal field 

 of the tegmina usually conspicuously lighter-coloured. [West 

 coast of Central Mexico.] 4. pacifica, sp. n, 



biol. CENTR.-AMER., Orthopt., Vol. II., January 1904. Hh 



