216 



MISSOURI BOTANICAL GARDEN. 



pollinator had almost completely disappeared, though some 

 spikes were yet blooming. 



In aspect, this variety differs from the typical Whipplei of 

 the mountains in not being cespitose, and in its thinner,quite 

 flexible, often broader and longer leaves. Its flowers are 

 similar to those of the type except that they are commonly 

 more or less brown-purple, and they are as variable in 

 form. All about Arrowhead, at the time of my first visit, 

 there were evidences of the work of a Fronuba in last 

 year's capsules, which were very abundant, and I conse- 

 quently expected to be able to study the work of P. macu- 

 lata in the opening panicles. I was, however, surprised to 

 see that the only Pronuba found on the plants of this 

 vicinity, though possessing the usual maculata structure, 

 was of a beautiful jet black color, and, with the exception 

 of a single specimen, in which the thorax was dingy white, 

 this proved to be the case with the thousands of moths 

 seen or captured about Arrowhead and in the valley to a 

 point near Irvington. I have called this rnelanic form P. 

 maculata, var. aterrima.* 



The females of this black Pronuba rest upon the ovary 

 with their heads toward the stigma, precisely like the typi- 

 cal maculata, while the males also commonly stand upon 

 the petals. Like the maculate moths, they are very alert, 

 and quite ready to drop from the flower and take wing 

 when disturbed. They are also active during the day, the 

 males, especially, running and flying from flower to flower 

 in quest of their mates ; and copulation is seen within the 

 flowers at all times of the day. 



The collection of pollen was witnessed several times, 



* Pronuba maculata, var. aterrima, n. var. Characters of the species, but 

 the chitinized parts smoky brown, and the scales of a dead black color 

 throughout, or a few pale ones near the tips of the primaries. Living as 

 a larva in the forming seeds of Hesperoyucca Whipplei, var. graminifolia, 

 the flowers of which are pollinated by the female imago. In the foot- 

 hills immediately north of San Bernardino, California, April, 189:!. 

 Types deposited in the Entomological collections of the National Museum, 

 the Agassiz Museum and the California Academy. 



