LECONTE— SYNOPSIS OF PTEROSTICHUS. 233 



With the preceding, one female. The thorax is more rounded on the sides than in 

 those above described ; the elytra are longer than in the next, and scarcely as wide 

 as the thorax ; the feet are black. 



23. E. latebrosus, brevior, thorace subtransverso, lateribus rotundatis, postice breviter sinuati.s, basi 

 subrugoso, linea transversa anteriore margini approximata, elytris striis punctatis, interstitiis sub- 

 convexis. Long. -45. 



Missouri Territory, Prof Agassiz; Illinois, Wilcox. I should consider this as the 

 same as the preceding but for the difference in form, which is evidently in favor of 

 their being different. Both sexes are much more robust than the female ovipennis ; 

 the only other difference consists in the deeper and strongly punctured elytral strife. 



24. E. constrictus, longior, thorace subtransverso, lateribus valde rotundatis, postice breviter 

 sinuatis, basi subrugoso, linea transversa antica margini sub-approximata, elytris profunde striatis, striis 

 punctulatis. Long. -5. 



Feronia constrkta Sq.j. Journ. Ac. Nat. Sci. 4, 147; Trans. Am. Phil. Soe. 4, 427; Lee. An. Ljc. 

 4, 344. 



Missouri Territory, abundant. The thorax is much more rounded on the sides 

 than in any of the preceding, the base is only about one half as wide as the apex. 



25. E. substriatus, latior, thorace transverse, lateribus valde rotundatis, postice Irevitcr sinuatis, basi 

 rugoso, linea transversa antica margini subapproximata, eljtris tenuiter striato-punctulatis, interstitiis 

 planissimis. Long. -57. 



Feronia [MoIojk] suhstriuta Lee. An. Lye. 5, 344. 



Missouri Territory and Santa Fe, abundant. The thorax wider than in the pre- 

 ceding, very much rounded at the sides, and less constricted at the base, which is 

 two-thirds as wide as the apex. The outer striae of the elytra are very indistinct. 



26. E. fatuus , thorace transverso, lateribus valde rotundatis, postice brevius sinuatis, basi rugoso, linea 

 transversa antica obliterata, eljtris tenuiter striato-punctulatis, interstitiis planis. Long. -67. 



Iowa, Mr. Wilcox, one female. Resembles very much the next species, bvit the 



sinuated part of the sides of the thorax is much shorter, and the hind angles although 



rectangular are not prominent. 



27. E. colossus, thorace transverso, lateribus valde rotundatis, postice sinuatis, angulis posticis valde 

 prominulis, linea transversa anteriore tenui, basi utrinque rugose punctato, elytris tenuiter striato- 

 punctatis, interstitiis subconvexis. Long. '75. 



Feronia (^Molops) colossus Lee. An. Lye. 4, 343. 



One male found near the Kansas River. This species scarcely differs from Say's 

 description of Feronia heros, (Journ. Ac. Nat. Sci. 3, 145) but it is so much smaller, 

 that I have not dared to consider it as the same. The species of this group are so 

 numei'ous and so very closely allied, that it is necessary to be cautious about applying 

 the names of previous describers. Say describes his F. heros as more than nine- 

 tenths of an inch long, and as having a convex thorax, neither of which will apply to 



59 



