100 GEO. H. HORN, M. D. 



P. linibata Fab., Syst. El. 1, p. 486. — Form of discoidea, and closely resem- 

 bliug it ill coloration. Aiiteunfe piceous, the three basal joints conspicuously 

 paler. Thorax also similar in form, but with a transverse depression of some- 

 what crescentic form, sometimes slightly deeper at the ends. Elytra very indis- 

 tinctly punctate and quite shining. Body beneath entirely yellow, the abdomen 

 sometimes slightly darker. Legs yellow, sometimes with the tips of the tibife 

 and tarsi darker. Length .14 — .26 inch. ; 3.5 — 6.5 mm. 



In the male the segments 2-3-4 are not very different in length, 

 being successively slightly shorter. The last segment is large, the 

 disc in front convex, near apex a deep fovea, beyond which the seg- 

 ment is prolonged in a truncate lobe limited each side by a deep 

 notch. Last dorsal segment truncate, slightly eraarginate, ciliate on 

 its edge. In the female the terminal ventral segment is oval, the 

 pygidiuni oval, but more acute. 



This species resembles discoidea so greatly superficially, that it is 

 not surprising that it has not been separated. It will be observed 

 that the thorax has a vague transverse depression in place of two 

 fovese, the antennae are shorter and stouter, sex for sex, than in dis- 

 coidea, the elytra smoother and more shining. The structure of the 

 last ventral of the male is notably different. 



As a rule, the three basal joints of the antennae are conspicuously 

 paler, while in discoidea, usually piceous. In the present species 

 the abdomen is yellow, and in discoidea usually more or less piceous. 

 While the legs here are usually all yellow, it is the rule in discoidea. 

 to have the tips of tibire and tarsi piceous. 



Occurs in District of Columbia, Virginia, Iowa, Texas. 



I». vittata n. sp. — Form of discoidea. Head black, shining, front yellow. 

 Antennse piceous, basal joint sometimes pale. Thorax yellow, one-half wider 

 than long, sides nearly straight, slightly convergent posteriorly, disc smooth, a 

 vague transverse depression of variable extent. Elytra piceous, side margin and 

 suture yellow, and a similar vitta of variable extent from the humeri to apex, 

 surface either quite smooth %, or sparsely finely punctate 9- Body beneath 

 yellow, abdomen usually piceous, sometimes yellow. Legs yellow, tibiae at apex 

 and tarsi piceous. Length .16 — .20 inch. ; 4 — 5 mm. 



In the male the ventral segments 2-3-4 are nearly equal in length, 

 the fifth much larger, convex in front, very deeply cupuliform behind, 

 at middle prolonged in a short truncate lobe limited each side by a 

 notch ; the last dorsal is truncate and ciliate. The ventral segments 

 of the female are as in limbata. 



In the female the antennss are of the usual filiform structure, while 

 in the male they are evidently thicker toward the tip. 



