Report of the State Entomologist 261 



Compared with the much better known pea- weevil, shown in Fig. 



17, obsoletus is not one-half so large, is 



more soberly colored, having less white 



on the wing-covers, and is without the 



white spot on the middle of the hinder 



part of the thorax and the two oval 



blackish spots which so conspicuously 



mark the exposed tip of the abdomen of 



Bruchus pisorum. In the latter the 



whitish hairs of the wing-covers form an Fig. it— The pea-weevil, Bkuchus 



oblique, interrupted, bent band behind fi^o^;^^ natural size and en- 

 ^ ' r > larged; 5, a pea containing the 



the middle. weevil. 



Description of the Beetle. 

 Say's description (loc. cit. sup.) of Bruchus obsoletus may be consulted 

 for more positive determination. It is as follows: 



Body blackish cinereous with a slight tinge of brown; antennae not 

 deepW serrate; thorax much narrowed^ before, cinereous each side, a 

 slight impressed dorsal line; base with the edige almost angulated, 

 central lobe almost truncate; scutel quadrate, whitish, longitudinally 

 divided by a dusky line; elytra with the intersticial lines having a 

 slight appearance of alternating whitish and dusky; on the middle of 

 the third intersticial line is a more abbreviated whitish line ; posterior 

 thighs with a black spine and two smaller ones. 



Length over one-tenth of an inch. 



The whitish or cinereous markings are not very striking; on the 

 elytra they may sometimes be traced into two obsolete macular bands. 



I obtained many specimens from the seeds of an Astralagus in 

 August. 



Prof. Riley has given in his Third Report on the Insects of Missouri, a 



detailed description of B. fabce, which may also be referred to. The 



features upon which he separates it from B. obsoletus of Say are these: 



We give them that by their aid, B. fabce, if it proves to be a permanent 



variety, may be identified from the comparison.* 



B. obsoletus is a smaller species, dark gray, with the antennae all 

 dark, the pygidium not rufous, the thorax with a perceptibly darker 

 dorsal shade so that the sides appear more cinereous, a white scutel, 

 and each interstitial line of the elytra with a slight appearance of 

 alternating whitish and dusky along its whole length. 



The Bruchus fabae of Prof. Riley. 



Following the description of B. fabce, to which reference is made 



above, the description being too extended to give it place here. Prof. 



Riley has written as follows: 



This insect has been for several years ticketed in some of the East- 

 ern collections by the name of B. fabce, or else what is worse, the 

 corruption of it, fabi. ****** 'jjje name was credited to 



34 



