Materials, Theie Taxonomy and Natural History 57 



concave. Length, 2 to 2.75 mm.; breadth, 1 to 1.35 mm. Incubation lasts 5 to 

 10 days ; average 7 days. 



First larval stage : Head, pronotum, and legs, black ; body bright yellow, 

 spiracula spots only present. Length at end of stage, 2.5 to 3.25 mm. 



Second larval stage: Exactly like first stage in all respects, except that 

 anterior edge of the pronotum may be brownish or yellow in variable degrees. 

 Length at end of stage, 3 to 5 mm. 



Third larval stage: Like second, except that pronotum always has anterior 

 portion yellow. Body color deep yellow. Length at end of stage, 9 to 14 mm. 

 Length of larval life from 12 to 25 days; average 15 days. 



Pupa: Pupates in the ground at a depth of from 1 to 5 inches. Pupa yellow, 

 spiracula spots present. Pupation lasts from 8 to 16 days; average 10 days. 



Length of ontogeny: 25 to 46 days ; average 32 to 35 days. 



Geoghaphical Distbibution. 



As far as information is available, this form is strictly limited to the Rio 

 Balsas Valley below the Mexican escarpment on the west, the Oaxaca-Guerrero 

 Highlands, and southward to the Isthmus of Tehauntepee (plate 5). I have 

 seen it in all its stages many times at the following locations: Cuernavaca, 

 Yautepec, Jojutla, Triente, Puente de Ixtla in the State of Morelos; Iguala, 

 Naranjo, Los Amates, Balsas, State of Guerrero; Cholula, Atlixco, Tatetla, 

 Matamoros de Izucas, Tlancualpican, State of Puebla; Oaxaca, Mitla. Tlaco- 

 lula, Tula, San Juan, El Parian, Tecomavaca, Venta Salada, State of Oaxaca 

 (Tower, 1906, p. 7) . The records of Guadalupe and Texcoco, valley of Mexico, 

 are of L. multitceniata, biotype of L. multitcBniata Stal. Added localities: 

 Mescala, Venta, Zopilote, Chilpancingo, Chilapa, Tetela de Eio, State of 

 Guerrero ; Ocotlan, Ejutla, State of Oaxaca, extend its known range well over 

 the Oaxaca-Guerrero Highlands, but I have no records from the Pacific slope, 

 and I have not found it as far south as the Isthmus of Tehauntepee, nor north 

 beyond the Eio Tepalcatepec Valley. 



Habitat, Ecology, Life Histoby. 



Living everywhere in regions having a long, hard, dry season and a short, 

 sharp, rainy season, two general periods occur — one of quiescence passed as an 

 adult in hibernation in cemented cells in the earth and the other in active growth 

 and reproduction. The beetles emerge from hibernation at the end of May or 

 early in June, begin breeding by the middle of June, and produce a generation 

 which emerges by the latter part of July, which again breeds at once and gives a 

 second generation, which emerges at the end of August or early in September. 

 The generation soon enters hibernation and remains dormant until the follow- 

 ing May. At Cuernavaca and Oaxaca this cycle is very regular, although there 

 is frequent overlapping and intercrossing of broods at all locations. Materials 

 from nature are, therefore, very frequently impure in respect to the reproductive 

 rhythm, and must be purified before utilization in experiments. 



SOUBCE OF MaTEBIAL. 



The materials for experimentation in this species have come from the follow- 

 ing localities, with the exception of a few unimportant strains : {a) Cuerna- 

 vaca: Stock No. 617, from Rancho de Basoco, to east of town, on a loma sepa- 

 5 



