REVISION OF ELEODTINI BLAISDELL. 15 



episterna, form between them the boundaries of a rather hirge fossa, 

 in the deep and someAvhat anterior wall of which is situated the meso- 

 thoracic stigma. This stigmatic fossa is situated immediately within 

 the mesosternal epimera under cover of the elytra. 



M etastermiTn short, the median part or hody is subquadrate, some- 

 Avhat equal in length to the abdominal intercoxal process, anteriorly 

 entering between the mesacetabula quite equally with the mesosternal 

 salient and forming with it the intersternal suture; the latter is either 

 straight or arcuate, according to w^hether the intercoxal processes are 

 truncate or more or less rounded — a variable condition even within 

 specific limits; posteriorly the border is transverse, not in the least 

 entering between the metacetabula. 



The sides of the body are produced laterally, much narrowed be- 

 tAveen the mesacetabula in front and the metacetabula behind to 

 expand somewhat triangularly more externally against the episterna, 

 as the aliv. The anterior borders of the ala^, laterad to the intercoxal 

 process, are arcuateh' reentrant to form the posterior moieties of the 

 mesacetabula ; the posterior borders of the ahie are less strongly and 

 arcuately reentrant to form the anterior boundaries of the metrace- 

 tabula. The basal borders of the ahv are very feebly reentrant and 

 rounded to fit the feebh' arcuate edges of the episterna, forming the 

 metasternal sutures, each extending from the external angle of the 

 mesacetabular recess in front to the external angle of the metacetab- 

 ulum behind. The anterior basal angle of the metasternal ala is 

 shut off from the externo-posterior angle of the mesosternum by the 

 mesosternal epimeron at the external angle of the mesacetabular 

 recess; the jiosterior basal angle of the ala is prevented from meeting 

 the first abdominal segment by the interposed epistenium at the ex- 

 ternal metacetabular angle. 



Mctaxtcnuil ephterinim. — P^longately subrhomboidal, slightly wid- 

 ening at middle, thence feebly narrowing to the posterior border, 

 about three times longer than wide and about three and a half times 

 longer than the mesosternal epimeron; base obliquely truncate and 

 connate with the posterior edge of the mesosternal epimeron, forming 

 the mesepimeral suture; internal border feeblv arcuate and connate 

 Avith the base of the metasternal ala; the external margin is straight 

 and ada})ted to the inferior epipleurai margin. The posterior edge 

 internally is somewhat inflexed at the external angle of the metace- 

 tabnlum. externally giving attachment to the small subacutely digiti- 

 form metasternal epimeron, which is feebly and iuAvardly arcuate, 

 resting in a small depression on the surface of the first abdominal 

 segment at the externo-anterior angle, and bounding the metacetab- 

 idum at its external angle. 



The mctathoracic stfigma is situated iumiediately opposite to the 

 posterior extremity of the metasternal episternum and under cover 



