1098 



FAMILY LIII. CHRY SOMELIDiE . 



e. Front of head normal, not inflexed, mouth anterior. 



/. Last dorsal segment of abdomen not exposed; middle ventral seg- 

 ments not narrowed. 

 g. Antenna? widely separated at base, usually more so than the 

 length of first joint. 



h. Front coxae rounded ; third tarsal joint bilobed. 



Tribe VII. Eumolpini, p. 1134. 

 hh. Front coxae transverse; third tarsal joint usually entire. 



Tribe VIII. Ohrysomklijst, p. 1149. 

 <jg. Antennae rather close together at base, inserted on the front; 

 front coxae conical and prominent. 



i. Hind thighs slender, adapted for walking. 



Tribe IX. Galeeuciwi, p. 1162. 

 ii. Hind thighs thickened, adapted for leaping. 



Tribe X. Halticlnt, p. 1177. 

 ff. Last dorsal segment of abdomen exposed and sloping downward ; 

 form of body robust, compact, subcylindrical. 

 j. Surface of body coarsely tuberculate above; antennae received 

 in marginal grooves on the lower side of thorax. 



Tribe V. Chlamydial p. 1114. 

 jj. Surface of body not tuberculate; antennae not received in 

 grooves. 



1c. Prosternum not separating front coxae; antennae short and 

 serrate. Tribe IV. Clythriai, p. 1112. 



kJc. Prosternum extending between front coxae; antennae usually 

 long and slender. Tribe VI. Cryptocephallnti. p. 1116. 

 ee. Front of head inflexed, mouth inferior ; form oblong, wedge-shaped, 

 broad and truncate behind; surface usually strongly pitted or 

 reticulated. Tribe XI. Hispini, p. 1223. 



del. Thorax and elytra with broad, expanded margins; head (in our spe- 

 cies) concealed ; outline of body elliptical or nearly circular. 



Tribe XII. Oassidlnl p. 1228. 



Tribe I. DONACIINI. 



Oblong, graceful beetles of medium size which occur upon the 

 leaves and stems of water-lilies, arrowhead, pond-weed, skunk cab- 

 bage, pickerel weed, reeds, sedges and other water-loving plants, 

 and hence are semi aquatic in habit. In form and general appear- 

 ance they resemble certain Cerambycidas and constitute a connect- 

 ing link between that family and the present. The larvae live on 

 the outside of the submerged roots of the plants above mentioned, 

 and obtain their supply of air through the tissues of the plant. 

 When about to change into pupas, they enclose themselves in silken 

 cocoons, a number of which are often found fastened in a row to the 

 stems or roots of the aquatic plants. The mature beetles are more 

 or less gregarious, and fly about on bright sunny days, alighting on 

 the leaves or flowers in numbers, 



