198 J. L. LECONTE, M. D. 



in adoptiiiEc. After separating as distinct genera the very small species, 

 which seem by the appendiculate claws to be allied to MonacJms, the 

 remaining species of our fauna may be divided into two sets, the first 

 of which is distinguished by the anterior margin of the inflexed flanks 

 of the prothorax being toothed or sinuate, and by several singular 

 male sexual characters specified below. The other set, or typical 

 Cryptocephali may be divided according as the anterior prosternal 

 lobe is prominent and carinate, or truncate and flat. 



§ 1. Bassabeus Hald. 



The front prosternal lobe is feeble, provided with a short apical 

 process, but not carinate ; the anterior margin of the prothoracic 

 flanks are toothed or sinuate beneath the antennae. In the % the 

 presternum is armed at the middle with a large erect compressed 

 process; the first ventral segment at the middle forms a large flat 

 plate, the hind angles of which rise into acute processes or spines ; 

 the fifth ventral is broadly concave, with a crest of curved erect hairs 

 each side of the concavity ; the first joint of the front tarsi is some- 

 times dilated, and is as long as the two following united. In the ^ 

 all these characters are absent, and the fovea of the fifth ventral is 

 large, deep and circular. 



The species may be tabulated as follows ; 



Elytra with numerous yellow spots 2. 



Elytra with four scarlet spots; (prothorax obtusely toothed beneath) 3. 



Elytra entirely yellow 4. 



Elytra vittate with black and yellow 5, 



2. — Edge of prothoracic flanks acutely toothed under the antennse; '^ J ; 



brunnipes Oliv.j clathratus Mels.j 3.8 — 5 nam.; Middle and Southern 



States 1. cougestus Fabr. 



Edge of prothoracic flanks* only feebly sinuate under the antennae; spots 



of elytra normal; % <^; guttatua Hald.j 3.7 — 5 mm.; Pa.; Ga.; 111. 



2. formostis Mels. 



a. — Elytra yellow spots confluent into bands; sulpkuripennis Mels. 



/3. — Elytra yellow, with three interrupted brown stripes. 

 3. — Prothorax opake, sparsely punctured; elytra with anterior band extending 



nearly to the suture, and apical spot; % first joint of front tarsi not 



broader; 9 head s]X)tted with white; % 2; notatus'PahT.1 Hald.; 4.5 — 



5.5 mm.; Atlantic States 3. cletrituis Oliv. 



a. — Ferruginous brown, elytra darker with spots as above, (type Olivier). 

 Prothorax smooth shining; elytra as above; 'J> first joint of front tarsi 



broader; % ^ ; 3.5 — 5.5 mm.; Mid. and West. States 4.inaiuinil'er. 



* SufiFrian describes the tooth of the prothoracic flanks as rectangular in 

 sulphuripennis, and obtuse in formosus. I can perceive no special diS'erence, 

 and I have therefore placed them as the same, giving precedence to the name 

 formosus over sulphuripennis, which is expressive only of certain varieties. 



