ART. '-'8 REVISION OF DISONYCHA NORTH OF MEXICO BLAKE 19 



allied to that species, it is a considerably larger insect with pro- 

 nounced pronotal callosities and with distinctly punctate elytra. In 

 coloring it usually differs from peiu-ylvanica in having a pale lower 

 front, pale femora, and a pale margin to the abdomen, as well as 

 three pronotal spots. Although Say gave as type locality the 

 " United States '\ he deir^cribed it in a paper on the insects collected 

 on an expedition to the Rocky Mountains, and it was probably col- 

 lected somewhere along the Platte River.^^ I have seen no specimens 

 from west of Kansas and Nebraska. D. 'pensylvanlca is not known 

 to occur west of the Mississippi, except in Louisiana and Texas. 



Possibly this is the species that Crotch had in mind in his short de- 

 scription of paUipes (see previous discussion under D. procera). 

 There is a dark eastern form of this in which the head, femora, and 

 undersurface are entirely dark. It is merely a color form, as both 

 dark and typically colored specimens are found in the same series. 

 It is readily distinguished from the small pensijlvanica by its distinct 

 elytral punctation. Say in his original description mentions a dark 

 form as a variety that occurs " near the Rocky Mountains." Dl- 

 sonycha limbicollis (LeConte), described from Sacramento, Calif., 

 may be only a dark Pacific coast variety of tmiguttata, but several 

 minor points of difference have led me to retain it as a distinct species, 



5. DISONYCHA LIMBICOLLIS (LeConte) 



PiATE 1, Figure 5 



Haltica limbicollis LeConte, Reports of explorations and surveys for a rail- 

 road route from the Mississippi River to tlie Pacific Ocean, vol. 9, no. 1, 

 p. 67, 1857; vol. 12, pt. 3, p. 67, 1860 (Sacramento, Calif.; type in LeConte 

 collection, Mus. Comp. Zool.). 



Disonycha limbicollis Crotch, Proc. Acad. Nat. Sci. Philadelphia, vol. 25, p. 64, 

 1873.— Blake, Bull. Brooklyn Ent. Soc, vol. 25, p. 212, 1930. 



Disonycha pemi.sylcanica var. limbicollis Horn, Trans. Amer. Ent. Soc, vol. 16, 

 p. 202. 1S89. 



Description. — Elongate oblong oval, somewhat shining, elytra 

 distinctly punctate; head dark, pronotum with a wide black band 

 and pale margin, elytra with sutural, median, and submurginal 

 vittae; undersurface and legs dark. Head with interocular space 

 more than half width of head; carina narrowly produced, frontal 

 tubercles well marked; surface smooth except for coar.se punctures 

 on each side about fovea, sometimes a small fovea in middle of 

 vertex; entirely dark except sometimes a pale streak over labrum 

 on lower edge of front. Antennae dark, third joint shorter than 

 fourth or fifth, which are subequal, the fourth slightly longer. Pro- 

 thorax about twice as wide as long, almost rectangular with sides 

 only slightly arcuate, distinct lateral callosities on each side, and a 



" See Barber, Ent. News, vol. 39, p. 15, 1928. 



