1864.] 121 



which are short and simple in both sexes. Palpi not reaching beyond 

 the front, scales spreading, hardly distinct from those of the front. 

 Clypeus short and broader in front than usual. Epicranium broad, 

 somewhat pointed above. Labrum narrow. Maxillae hardly longer 

 than the head. Body stouter than usual. 



Primaries narrow, much produced towards the apex. Costa convex 

 at the outer third ;. apex acute ; outer margin one-third shorter than 

 the costa, 2nd subcostal arched, running near the 3rd. Upper branch 

 of Brd short, one-half as long as the lower. Space between the median 

 nervules in both wings regularly semi-oval, not so acute art the end as 

 usual, since the nervules are a little more bent outwards at their origin 

 than usual. 



Secondaries subtriangular, produced towards the apex ; costa slightly 

 convex, a little bent in the middle; outer margin convex, not reaching 

 to the tip of abdomen. Legs stout ; femora densely pilose, scales short. 

 Tibiae and tarsi naked. Four hind tibial spurs of moderate size. Tarsi 

 thickly spined beneath. 



Pyrrharctia Isabella. 



Phaloena Isabella Smith, N. H. Lep. Ins. Ga. p. 1.31. Tab. 66. (1797). 

 Arctia Isabella Harr., Cat. Ins. Mass. (Hitchcock's Rt.) p. 591. (18.33). 

 Rt. Ins. Mass. p. 253. (1841). Third ed. fig. 170 larva. (1862). 

 Walk., Cat. Lep. B. M. III. p. 611. (1855). 

 Spilosoma Isabella Clem., Proc. Acad. Nat. Sci. Phil. p. 531. (ZSTov. 1860). 

 Arctia Isabella Morris, Synopsis hep. N. Amer. Appendix, p. 340. (1860). 

 Spilosoma isabella Saunders, Synopsis Can. Arctiad.T:, p. 16. (1863). 

 N. Y. (Edwards). Mass. (Sanborn, ShurtlefF, Scudder). Maine (A. 

 S. P. Jr.). C. W. (Saunders). 



Pyrrharctia californica n. sp. 



This species would at first sight be easily confounded with P. mibnUa, 

 but the head is much larger, and the body much stouter generally. 

 The costa is much more convex, apex not so much produced ; outer 

 margin a little concave beneath the apex. Three transverse lines very 

 obsolete, not so much waved as in P. hahe.lla. Primaries of a deeper 

 yellow. Secondaries: costa much bent in its middle; slightly concave 

 below the apex. Nervules and margin roseate, within pale yellow, but 

 much darker th;in in P. isabella. Beneath a costo-apical spot is visible. 



Length .85. Exp. wings 2 inches. 



San Francisco, Cal. (Mus. Comp. Zobl. x\. Agassiz.) 



