555 



Tetracis ^grotata Guenee. Plate 13, fig. 65. 



Tetrads agrolata Gueu., Phal., i, 141, 1857. 



Walk., List Lep. Het. Br. Mus., xx, 173, 1860. 

 Chocrodts a-grotata Pack., Proc. Bost. Soc. Nat. Hist., xiii, 382, 1871. 



8 <f and 2 9. — The wings are less falcate than in T. truxaliata, and the 

 median angle of both wings is slight, but with a slight tooth between the apex 

 and central large tooth, while the wings are without the usual well-defined 

 angulated line on their outer third, and the male antenuse are simple. Body and 

 wings of a uniform pale light fawn-color; wings almost white beneath. Head 

 with thick hairs on the vertex, the scales being longer than usual; just below 

 the antenna?, a dark-brown band ; below a little paler than the vertex. Palpi 

 tipped with brown. Antenna? concolorous with the rest of the body. Wings 

 densely speckled with brown ; an inner, curved, very slightly dusky line, with 

 five or six black venular dots, and a similar line going from just beyond the 

 middle of the hinder edge, following a sinuous course to the costa near the 

 apex, with a black dot on each venule. A few minute black dots on the base 

 of the fringe, which is concolorous with the rest of the wing. A slight discal 

 dot on both wings, that on the fore wings small but diffuse, that on the hind 

 wings a minute black dot. Hind wings the same as the anterior pair, the 

 speckles being arranged in a faint band, straight, crossing the middle of the 

 wing ; an outer curved row of black dots parallel to the outer edge. Beneath, 

 dull white ; costa and antenna?, half of the fore wings, together with the 

 costa and the outer half of the hind wings sprinkled with black scales, and 

 a row of dots parallel to the outer edge of the wing near the edge; discal 

 dots as above, but larger and much more distinct. Fore legs dusky in front; 

 tarsi of hind and middle legs dusky ; otherwise white. 



Length of body, 6, 0.K5, 9, 0.80; of fore wing, J, 0.83, 9, 0.95; 

 expanse of wings. 1.70-2.00 inches. 



Sanzalito, Cal. (Behrens); Mendocino City, San Mateo, Cal. (A. Agassiz, 

 Mus. Comp. ZooL). 



This common species varies in the tint of the wings, and the outer line 

 of dots varies in distinctness and degree of sinuosity. In one specimen, the 

 outer band on the fore wings divides into two; the inner, opposite the discal 

 dot, being a broad, wavy band, situated half-way between the dot and the 

 outer band. 



Several specimens received from Mr. Behrens show that this species 



