40 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 70 



extreme apex pale. Another series of specimens froin Florida are 

 entirely deep chocolate brown in color, with no distinctly paler 

 margins or apex. 



OedioivychAs ohsidiana in its typical bhick lonii has long been 

 confused with quercata^^^ Both species were described by Fabricius, 

 ohsidicma as shining black with margin of thorax and tip of elytra 

 and legs pale, and quercata as with head and thorax ferruginous and 

 elj^tra black, with a ferruginous margin. Olivier gives two figures^- 

 showing these differences. The most striking characters of ohsidiana 

 are its darker head and pronotum and its typically pale apical pat- 

 tern and paler legs. It differs also in having larger, more closely 

 set eyes. In quercata the interocular space is about half the width of 

 the head, whereas in ohsidiana it is less than half, approaching one- 

 third the width of head. The elytra in ohsidiana are not so wide and 

 rounded and the rounded callosity at base of each elytron at scutellar 

 angle is very prominent. The punctation is finer and the surface 

 more shining. 



A cotype was examined by the writer in the Bosc collection at 

 Paris. 



OEDIONYCHIS OBSmiANA FLAVA, new variety 



Head more or less piceous even in palest forms, pronotum with 

 dark blotches, usually in form of two oblique marks on either side, 

 variable in size, elytra very variable in pattern, sometimes pale yel- 

 low with piceous spots on humeral prominences, sometimes this dark 

 marking extending across base of elytra, spots laterally and medially, 

 frequently uniting to form band across middle of elytra, and usually 

 a band or remnant of band at apical fifth. 



Type and 20 faratypes.—Q^i. No. 29159, U.S.N.M. 



Type locality. — Mobile, Ala. 

 • Distribution. — Alabama, Louisiana, Tennessee, Illinois, Arkansas, 

 and Kansas. 



Described from 21 specimens in the National Museum from Ala- 

 bama, Louisiana, Tennessee, and Arkansas. 



This pale form intergrades with typical ohsidiana through speci- 

 mens with spots and fasciae of varying width, the elytra sometimes 

 being almost entirely piceous except for j^ellow streaks or spots at 

 basal third, again with three broad fasciae across elytra resembling 

 in pattern Oedionychis scalaris. It was described and figured by 

 Horn as a color variety of quercata.-'^ A series of specimens from 

 Alabama, also two from Arkansas in the National Collection, show a 

 perfect gradation of pale yellow forms to typical black ohsidiana. 



" Horn, Trans. Amer. Ent. Soc, vol. 16, 1889, p. 194. 



^Ent., vol. 6, p. 691, pi. 2, fig. 32, and pi. 3, fig. 40. 



28 Horn, Tians. ,\mer. Ent. Soc. vol. 16. ]889. pi. 6. fig. 4. 



