186 
PROCEEDINGS OF THE ACADEMY OF 
E. im munis, oblonga, nigra nitida, capite modice, thorace subtilius et 
parce punctato, lioc qnadrato latitudine liaud breviore, antice paulo latiore, 
lateribns rotundatis, angulis anticis subacutis posticis obtusis, elytra ovalibus 
(maris parum, feminae sesqui) tliorace latioribus, modice convexis, postice ob- 
tuse subacuminatis valde declivibus, fortiter striato-punctatis, saepe fere sul- 
catis, interstitiis parum convexis parce punctatis. Long. -68 — -72. 
Sonora, Dr. Webb, and Mr. Scbiott. Nearly of the same form as E. s o r o r, 
but readily distinguished by the thorax being more narrowed behind, almost 
as inE. quadricollis; the punctures of the rows of the elytra are some- 
times placed in distinct grooves, while in other specimens the surface is even. 
The femora of both sexes are altogether unarmed, and the prosternum is per- 
pendicular at tip and not mucronate ; the abdomen is very sparsely punctured 
and faintly rugous, 
E. omissa, longiuscula, nigra, subnitida, thorace latitudine sub-breviore' 
parum convexo, lateribus late rotundatis, postice subangustato, subtiliter 
parce punctulato, elytris thorace parum latioribus postice declivibus et oblique 
angustatis, parce subtiliter fere inordinatim punctatis, prosterno apice horizon- . 
tali, ac3ito, femoribus muticis, crassiusculis. Long. -63. 
One male, San Diego, California. Resembles very closely in form the male 
ofE. quadricollis, but besides minor differences, it is much less punctured, 
the prosternum is horizontally mucronate, and the thighs are thicker, 
X. 
E. nigrina, elongata, nigra subopaca, thorace subquadrato, postice an- 
gustato, lateribus late rotundatis, apice fere truncato, modice convexo, subtili- 
us sat dense punctato, elytris thorace parum latioribus, postice declivibus et 
oblique angustatis, inordinatim subtilius punctatis, punctis prsecipue ad latera 
muricatis et brevissime setiferis, pedibus muricato-punctatis, femoribus anticis 
obtuse sinuatis, prosterno abrupte truncato. Long. '74 — -80. 
Black Hills, Nebraska, Dr. Hammond ; Santa Fe, New Mexico, Mr. R. C. 
Kern. The female is a little broader than the male, but does not differ con- 
spicuously in form ; the anterior femora are not dentate, but only slightly si- 
nuate on their anterior margin. The punctures of the thorax are nearly equally 
distributed. 
XI. 
E. ventricosa, atra subnitida, capite parce, thorace subtiliter punctato, 
hoc transverso, antice modice, postice parum angustato, lateribus rotundatis, 
angulis anticis acutis, ad basin late rotundato, elytris ovalibus convexis, ad ba- 
sin vix late emarginatis, humeris vix acutis, thorace sexus utriusque plus 
sesqui latioribus, postice declivibus (maris breviter caudatis, femin?e obtuse 
vix acuminatis) plus minusve striato-punctatis, interstitiis uniseriatim parce 
punctulatis. Long. '108 — -14. 
Texas, near the Rio Grande. The punctures composing the strise of the 
elytra vary very much in size ; sometimes they are very large, while at others 
they are hardly different from the more distant interstitial punctures. The 
anterior femora of the male are armed with a long acute curved tooth, those 
of the female are slightly sinuate. The prosternum is compressed behind, and 
perpendicularly truncate, rising into a very small cusp. The abdomen is 
hardly rugous or punctured. 
xn. 
E. Haydenii, elongata nigra, nitida, thorace latitudine longiore, lateri- 
bus late rotundatis, disco modice convexo, parce subtiliter punctato, elytris 
confertim subtilius seriatim punctatis elongato-ovalibus, postice late attenua- 
tis, dorso parum convexis, lateribus abrupte inflexis, prosterno mucrone acuto 
parvo, femoribus muticis. Long. 1-04. 
One specimen from the Loup Fork of the Platte, Dr. Hay den. Related to 
[Oct. 
