38 IOWA STUDIES IN NATURAL HISTORY 
ostiolar canal terminated by a broad, rounded lobe. The more 
detailed differential characters are also herewith appended : 
Elongate oval. Head widely rounded, the margin narrowly recurved, 
with sparse hairs only; tylus as long as lateral lobes; bucculae rather 
widely separated anteriorly, gradually becoming higher posteriorly and 
enclosing the first segment of the rostrum which reaches nearly or quite to 
mid-coxae; second segment of rostrum longest, the third segment longer 
than the fourth. Antennae with basal segment stouter than the second 
segment, a little reduced at tip; second segment slender, either longer or 
shorter than third which is thickened towards tip; fourth longer, fifth 
longest, both subfusiform. Pronotum wider than long, slightly convex, 
the lateral margins almost straight, the edges recurved; anterior margin 
broadly sinuate, the posterior margin nearly truncate. Scutellum longer 
than broad, sharply narrowing towards apex, the tip narrow, acute. Hem- 
elytra broad, depressed; apical portion of costal margin curved thus expos- 
ing the posterior part of the connexivum; posterior margin oblique, 
slightly areuated. Ostiolar canal long, slender, about two-thirds the 
length of episternum and with a broad, rounded lobe at tip. Legs nor- 
mal, the anterior tibiae only moderately expanded. 
As suggested by Signoret (Ann. Ent. Soe. France, IIT, Ser. 
6, 33, 1883), most of the characters of the genus are more or less 
meeative JOUb 17. - ee on voit que les Geotomus s’en séparent 
trés facilement et offrent de particulier que, sans aucun ecarac- 
tére réel, on peut cependant trés bien les considérer comme con- 
stituant un bon genre.’’ 
Geotomus robustus (Uhler) (PLATE V, Figure 2) 
1877. Melanaethus robustus Uhler, Bull. U. S. Geol. Geogr. Surv., III, 390. 
1883. Geotomus robustus Signoret, Ann. Soc. Ent. France, III, Ser. 6, 59, PIL. 
4, fig. 168. ; 
1904. Geotomus robustus Van Duzee, Trans. Am. Ent. Soc., XXX, 25. 
1911. Geotomus robustus Zimmer, Univ. Neb. Contrib. Dept. Ent., no. 4, 24. 
1916. +Geotomus parvulus Stoner, Proc. Ia. Acad. Sci., XXIII, 304. 
Widely oval, somewhat flattened above. General color deep black, some- 
what shining; apices of hemelytra deep brownish black. Head broad, 
densely punctured, depressed near anterior margin which is almost reg- 
ularly semicircular with the edge elevated; occiput smooth. Antennae 
stout, reddish brown, the segments darker at the middle; second segment 
slightly shorter than third; fourth segment longer than third and fifth 
segment longest. Rostrum reddish brown, reaching mid-coxae; second 
segment longest, fourth shortest. Pronotum a little narrowed and rounded 
anteriorly, the surface closely, coarsely punctured except on disk which 
is almost smooth; transverse impression faint, distinct only at sides; anter- 
lor submargin with a row of fine punctures but the margin itself is im- 
punctate; humeri and posterior submargin elevated. Scutellum long, 
broad, basal portion remotely, rather coarsely punctate, the disk feebly 
