CRIOCERID^. — DONACIA. 26T 



nearly so, apMdivorous : — some few subsist upon fungi, and others 

 (as those of the Halticse) are extremely injurious to the agricul- 

 turist by destroying the seminal leaves of the plants immediately 

 they appear above the surface, sometimes devastating whole acres 

 by their numbers. 



Subsection I. — Eupoda, Latreille. 



Body generally elongate : antennw not longer than the head and thorax, sub- 

 filiform, the terminal joints sometimes a little incrassated : labium mostly 

 entire: mandibles entire at the apex or bifid: maxillw with the outer lobe 

 thickened and entire : eyes simple, sometimes a little eraarginate : head deeply 

 inserted in the thorax, the latter mostly cylindric, or subquadrate, narrower 

 than the elytra, which are elongate, sometimes depressed : legs moderate : 

 Jemora, especially the posterior, more or less clavate, and elongate, sometimes 

 dentate : tibice simple, with spurs at the apex : tarsi tetramerous, rather short, 

 the penultimate joint bilobed, the lobes elongate. 



The indigenous species of this subsection compose 



Family XLIX— CRIOCERID^, Leach. 



Which may be distinguished by the above characters, and contains 

 the following British genera : 



AntenncE articulis fere omnibus elongatis. 



Elytra baud mucronata : ... 386. Donacia. 



mucronata : . - . . 387- Macropalea. 



articulis brevibus. 

 Pa^i maxillares filiformes ; . • . . 389. Crioceris. 



extrorsum crassiores. 

 Thorax glaber, baud tuberculatus : . . 388. Orsodachna. 



utrinque tuberculatus : . . » 390. Zeuggphora. 



Genus CCCLXXXVI. — Donacia, Fabrkius. 



Antennae approximating, Avith nearly all the articulations elongate ; much longer 

 than broad, subcylindric, or conic- cylindric, with the basal joint longer and 

 stouter, and obconic, the second abbreviated. Palpi four, filiform : mandi- 

 bles bifid at the apex : maxillw membranaceous, bilobed : labium with the 

 superior margin entire: head porrect, united to the thorax by a distinct neck: 

 eyes prominent, semiglobose, entire: eA/ifra subtrigonal, narrowed behind, and 

 often truncate at the apex : femora elongate-clavate, especially the posterior, 

 which are frequently dentate : tarsi short : body generally adorned with bril- 

 liant metallic colours. 



