SAW HORNED WOOD-BEETLES. 1>5 



(MIS beetles) inhabit wood aud bark iu an advanced state of decay. In 

 accordance with this position, they are usually the first insects to attack 

 trees which have been injured by sun-scald, or wliicli have otherwise 

 liiid their vitality weakened. 



The following" are the genera of 15iii»'(Sii,la' : 



A. Himl coxal plates* much widuiiod at their inner extrouiities. JSody oblong ami soniowliat tin- 



preaseil, and more or less elliptical or uannwod al the two extremities. Si/.o usually large or 



uiediuiu. {JUiijrcxlides proper.) 



V>. The epiinera (or binder side pieces) of the raetasternuin triangular and exposed; prosternuni 



acutely angulatod behind. 



C. Me.sosternum and nicta.sternuni united williout suture. Fir.st Joint ol' the bind tai-si a.s long 



•M» the second and tbird united. Size large or very large ('llAl.coi'liouA, 7 sp. 



C C. Mesostemal suture distinct ; size ratbei' large or medium. 



I). Elytra tapering to a jHtiut and slightly separated at tkeir tips ; Istjoint of hind f aisi scarcely 



longer than '2(1 DlCEltf A, 'ii sp. 



U I). Elytra moderately narrowed behind. 1st tarsal Joint ehnigated Blll'lilcsTls, 'ill sp. 



H 1{. ICpinieraof the meta-sternum partly covered by an anterior prolongation of the margin of I ho 

 abdomen. Prosternuni acutely angulatetl behind. 

 E. Front with a pit or dopressiou for the insertion of tlie ante^na^ Size moderate: 



C1IKY.SOHOTIIKIH, 4:1 sp. 



E. Front without pit. Size snuvll. 



F. Thorax weaving at its Junction with tbe elytra Mki.anoiiiii.a, 1ft sji. 



F F. Thorax cut straight across behind Antuaxia, 14. 



A A. Hind coxal plate.s but little widened at their inner extremities. Size never alio ve medium ; 

 usually .small or very snuill. 



G. Front without pits for the insertion of the autouine. Thorax straight behind. Scu- 



tellum none. Body clothed with short erect hairs. Colors often variegated : 



ACM^KODKUA, 2:j sp_ 



G G. Front pitted for antennas. Thon-vx angulated behind. Scutellnm distinct. Jiody not 

 hairy. 

 II. Body elongated, narrow, almost cylindrical. Prostenuim without grooves for the 



reception of the antenna} Agrilus, 40 sp. 



H H. Body short and broad. Prostemum with grooves for the antenna\ Tarsi very 

 short. 



I. Body ovate; scutellimi small; tibia- slender Bkachys, 8 sp. 



I I. Body sub-triangular; scutel large; tibia; dilated Mktoxiits, 2 sp. 



The largest N. A. species of Buprestis is the Chalcophora vin/imensis 

 of Drury, nearly or quite an inch in length, of a dark coppery or black- 

 ish color, and a very uneven surface, caused by elevated linos and div 

 j)resse<l square-shaped spots. The larva inhabits the trunks of difterent 

 kintls of pine trees, and the perfect insects are to be found, therefore, 

 only in pine growing regions. The Dicerca divaricaia, Say, is three- 

 quarters of an in(;h or more in length, copper colored, with a granulated 

 surface. It is distinguished at once by its tapering elytra, separated at 

 the tips. Its larva bores into the trunks of cherry and i)each trees. 

 We have another, smaller and more obscure species, the 7>. lurida, Fab., 

 the larva of which inhabits the hickory. The Chri/.sohothri.s fcmorata, 

 (Fig. 42) an obscure bronze-black species, rather less than half an inch 

 in length, is the parent of the well known Jiatheaded borer, so injuiious 

 to apple trees, and also to the soft maple. 



* The hind coxal plates are the flat and uaiTOW transverse pieces which border the under side of the 

 thorax behind, and are separated by a suture from the metasternum. They are marked C X P in 

 Fig. 3. 



