266 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.49. 



Calvert ^ writes that in a large series of Mexican and C^entral American 

 material such slight intergrading differences are to be found, but 

 Doctor Ris, after comparing a series of the Yakima specimens with 

 the series of grandis in his collection, considered calif ornica a good 

 species. 



Figures and 7 show ventral and lateral views of the male appen- 

 dages. 



As Archilestes is a peculiar genus and contains only these two 

 species, I have taken this opportunity to figure some of the grosser 

 anatomical peculiarities. Figure 9 shows the chitinized parts of the 

 sexual apparatus in the second segment of the male, lateral view. 

 The dorsal or inner arm of the penis is held by a single pair of heavy 

 supports. The parts supporting its inner tip are not chitinized. The 

 external tip of the penis has a small, fleshy, ventral lobe and a large, 

 almost circular, disc-shaped dorsal lobe. (See fjgs. 10 and 11.) A 

 ventral view of the second segment in the male is shown in figure 8. 



Figure 13 shows the mesostigmal lamina of the female, which is 

 rather complex. Figure 12 shows the pro thorax of the female, which 

 does not differ from that of the male. Figure 14 is a lateral view of 

 the ninth and tenth segments of the female abdomen with their 

 appendages. 



Archilestes in the Yakima Valley is an autumnal insect. When it 

 first appears, the following summer species are disappearing: Agrion 

 aequahile yakima, Argia emma, Argia vivida, Opliiogom'pJius severus, 

 AesliTKh multicolor, Macromia magnijica, Lihellula forensis, and Pla- 

 themis lydia. 



The first specimens of Archilestes were taken July 27. These were 

 few in number and all very toneral. On August 3 perhaps as many 

 as a hundred were seen in the willow glades branching from the main 

 channel of the creek, and on August 7 Archilestes were common. 

 The breeding season for Archilestes lasted, then, until about Septem- 

 ber 14, when several frosts occurred and collecting did not begin mitil 

 10 o'clock in the morning and was practically over at 2 o'clock. At 

 this date the only other dragonflies on the wing were Lestes congener, 

 Ischnura perparva, Ischnura cervula, Aeshna palmata, Aeshna umhrosa 

 ocddentalis, Sympetrum pallipes, and Sympetrum vicinum. At this 

 late date Lestes congener, Archilestes californica, Aeshna palmata, 

 Aeshna umhrosa ocddentalis, and Sympetrum vicinum were at the 

 height of their season. Six weeks later stragglers of these species 

 were still on the wing along Yakima River. 



During August, or until active breeding began, the individuals of 



this species with wings held loosely open were usually fomid hanging 



.on the leaves and stems on the sunny side of willow and alder bushes. 



Here each appeared to have its favorite position, from wliich it would 



1 Calvert, P. P. The Odonata of Baja California, Mexico. Proc. Cul. Acad. Sci., ser. 2, vol. 4, 1894, p. 555. 



