Materials, Their Taxonomy and Natural History 37 



Geographical Distribution. 



Mexico (plate 3), on slope of eastern and western escarpment, at altitude of 

 3000 to 6000 feet; from the state of Vera Cruz, Mexico, at Cerro El Borrego, 

 Cerro Escamela ; Sumidero near Orizaba, Jalapa, Cocomatepec, Huatusco ; 

 Mitla, Tlacolula, Ejutla, Oaxaca, Villa Alta, state of Oaxaca ; Guanajuato 

 (Duges), canyon of Eio Grande de Santiago, at many points below Cascada de 

 Janacatlan in Jalisco; Tepee, El Cora, territory of Tepee; and it is probably 

 distributed along the Pacific coast to the Gulf of Lower California and south 

 into Oaxaca-Guerrero highlands. On the east it is probably distril)uted through 

 the foot-hills and north to the Rio Panuco Valley. 



Habitat. 



The general distribution of this species is shown in plate 3. It is not a gen- 

 erally distributed form, but, as far as I have observed it, is always local, limited 

 to narrow habitats, either on hillsides, the edges of the steep-walled barrancas 

 that cut the edge of the Mexican Plateau, or in the immediate vicinity thereof. 

 It apparently is distributed along the eastern and western edges of the plateau, 

 on the east as far north as the valley of the Eio Panuco, and on the west it 

 apparently reaches nearly to the head of the Gulf of California ; at least, good 

 museum material from the Pacific coast of Mexico is of this type. On the south, 

 in the deserts of the Tehuacan district, it is modified into the geographical 

 variety rugosa, and on the Oaxaca-Guerrero highlands it again assumes its 

 typical form. South in Chiapas it occurs typical in form, and apparently it 

 extends southward into Guatemala ; at least, museum material from the plateau 

 region of Guatemala is apparently of this same type. 



SouBCE OF Material. 



Living material for experiment has come from (a) the east side of Cerro el 

 Borrego and from the southern end of Cerro Escamela near Orizaba, Vera 

 Cruz. Stocks were obtained as follows : No. 815 in August 1903; No. 816 in 

 May 1904; No. 817 in June 1905; No. 818 in August 1907; No. 819 in May 

 1909. (b) From the canyon of the Eio Grande de Santiago at point due north- 

 west of Guadalajura ; in Jalisco known as " la l)arranca." Stocks were obtained 

 as follows: No. 800 in September 1903; No. 801 in June 1905; No. 802 in 

 May 1907. (c) Two kilometers north from Tlacolula in Oaxaca. Stocks were 

 obtained as follows: No. 810 in June 1904; No. 811 in August 1909. 



I have used the material from Cerro el Borrego in the larger part of my 

 experiments. The materials are gametically alike at all three locations. 



HABITUDINAL variety rugosa NOV. VAR. 

 (Plate 2, figs. 5, 6, and 7.) 



Like diversa in form, color, and markings, but larger. Distinguished from 

 divcrsa by coarse punctations of head and pronotum and the very large irregular 

 punctures along the edges of elytral stripes, which are two to five times as large 

 as in diversa. Elytral stripes vary from a complete shiny black stripe to almost 

 complete absence thereof. Some examples show only faint brownish tinge in 



