194 BULLETIN 63, UNITED STATES NATIONAL MUSEUM. 



between the groove and cavity; the tarsal grooves are nsually more 

 contracted and more apt to be roughly sculptured. 



The relative widths and lengths of the tarsal elements, abdominal 

 segments, and sterna are about the same as in the preceding variet}^, 

 and the analysis of its exoskeletal characters indicates its truly inter- 

 mediate position. 



ELEODES SULCIPENNIS Mannerheim. 



Number of specimens studied, 54. 



Type in the JNIus. Imp. Acad. Scient. St. Petersburg. 



Type-locality is (northern) California. 



Salient type-chitj'acters. — Elongate. Thorax subcordate, sides nar- 

 rowly reflexo-marginate, finely punctulate, elytra oblong and deeply 

 sulcate, posteriori}' very slightly dilated, apex attenuate and strongly 

 declivous (Mannerheim). 



Diagnostic characters. — Quickly separated by the strongly sulcate 

 elytra. 



Some specimens from Colorado are intermediate between ohscura 

 and si/lcipennis, and liave the scabrous elytra of the former and the 

 distinct sulci of the latter. 



LeConte described a female collected in New Mexico by Captain 

 Pope as deleta. It was onl}' an intermediate variation and can be 

 placed as fornfia deleta.^ connecting dlspersa and ohscara. It was 

 characterized by LeConte as follows: Form of sulclpentiis, absence 

 of elytral grooves, except at the sides behind the middle, where some 

 faint traces are seen; the punctures are subnuiricate and arranged in 

 stria? distinct on the back, confused at the sides; between the rows 

 are distinct punctures as in ohscura; posteriorly abruptly declivous 

 and furnished with rows of tubercles, alternately large and snuill, 

 the latter corresponding to the strise of the anterior portion. Ante- 

 rior femoral teeth very obtuse. 



Other specimens, male and female, collected in Arizona, which are 

 the heterotype of sulcipennis, were also described by him under the 

 name arata. 



These strongly developed specimens can be labeled forma arata, 

 and may be recognized from the following brief description. 



ELEODES ARATA LeConte. 



Form of sidcipennis, thorax more convex, less flattened and less 

 punctured at the sides, and more finely margined ; elytral grooves 

 deeper, interstices smooth and shining, with much fewer scattered 

 punctures. 



The student will recognize the five forms, just considered, as ex- 

 pressions of variations in the same species, and these forms may be 

 arranged in the following morphological sequence: dispersa, deleta, 



