Materials, Their Taxonomy and Natural History 31 



even as somatic aberrations. It would be interesting to know how many of the 

 rare species varieties and instances of groups of closely allied species described 

 as inhabiting the same area are of this character. 



Study of actual material in the field, in life, is absolutely essential for all 

 genetic studies, and this must be done in many localities through a series of 

 years or generations. From different localities samples of the population must 

 be taken, tested by breeding under some standard set of conditions, and these 

 two sets of observations will eventually give the only true basis for the correct 

 determination of the nature and quality of the materials used for experiment. 

 This has been the general and inflexible plan in all of my work. 



In its application I have tried to go, and in the main have personally gone, 

 several times over the entire range of each species, collecting data and materials 

 in many localities, and each location was visited again in subsequent years. This 

 has given extensive data of distribution, ecology, and the differences in nature. 

 From many locations materials were tested under standard conditions, and the 

 gametic constitution of the species in the locality determined. This data, plus 

 that from observation in nature, gave the basis for thorough knowledge of the 

 nature of the materials used in this experimental investigation of evolution. 



SPECIES AND SUBDIVISIONS OF THE LINEATA GROUP. 



In nature I have found and tested the following species and their minor 

 divisions, which I have arranged in two divisions, as follows : 



A. Elytral markings edged with an irregular double row of impressed punc- 



tations. 

 Undecimlineata division: 



(1) L. panamensis n. sp. Q \ r " CT' 

 L. guatemalensis n. sp. — — "^^ • ir^ .*> 

 L. undecimlineata Stai. 



Saltation: abrupta nov. var. 

 L. diversa n. sp. 



Habitudinal variety: rugosa nov. var. 

 L. angustovittata Jacoby. 

 L. sigyiaticollis Stai. 



Biotype: nigropunctata Sturm. 

 Multitseniata division : 



(2) L. multita'niata Stai. 



(1) Habitudinal variation : multitwniata Stkl. 

 Recurrent mutation: melanothorax StSl. 

 Saltation: tacubayansis nov. var. 

 Biotype: obscura nov. var. multilineata Stil. 



(2) Habitudinal variation: variabilis nov. var. 

 Recurrent mutation: melanothorax StM. 



(3) Habitudinal variation: intermedia nov. var. 

 Recurrent mutation: melanothorax Stai. 



L. oblongata n. sp. 



Biotypes: (a) red, (b) orange, (c) yellow. 

 L. rubicunda n. sp. 

 L. decemlineata Say. 



Saltations: pallida nov. var., defectopunctata, minuta, tortuosa. 

 melanicum, rubrivittata. 



B. Elytral stripes edged with single even regularly placed row of impressed punc- 



tations. 

 Juncta division: 



L. juncta Guer. 



Habitudinal variation: texana Sch. 

 L. defecta St§.l. 

 L. tumamoca n. sp. 



