250 THE CANADIAN ENTOMOLOGIST, 



abdomens and long legs ; (3) the flattened, elongate larvae of the leaf- 

 eating Gallerucini and Halticini, which also always possess anal prolegs ; 

 (4) the very elongate, cylindrical root and stem mining foims of the last 

 mentioned tribes ; (5) the thin larvie of the Hispida?, with their flat, 

 wedge-shaped heads, rudimentary legs (though sometimes apodous) and 

 abdomen deeply serrated laterally ; and (6) the Cassidaj with their sharp, 

 spine-like lateral tubercles and long ffecifork bearing its mass of 

 excrement over the body. 



The larvje of the Donaciince have, however, a form quite distinct 

 from any of these, though resembling most closely - as in many other 

 respects — the Criocerini, which in turn are nearest the Chrysomelini. 

 The body is nearly cylindrical, and forms a distinct, even arc. The head 

 is from one-third to one-half the width of the prothorax, into which it is 

 more or less sunken. The body gradually enlarges to the sixth and 

 seventh abdominal segments, and then tapers abruptly caudad. D. 

 piscatrix is 13 mm. long by 3.75 mm. across the sixth abdominal 

 segment, the head being .66 mm. wide and the prothorax 1.5 mm. The 

 segments and folds are quite sharply distinct. 



The coloration is that common to mostsubterrestrial larv?e, the body 

 being a yellowish-white, and the head, articulations of the legs, spiracles, 

 and plates upon the eighth abdominal segment, dark brown. 



Just behind each antenna are found four small black ocelli, and another 

 occurs below it. The antennae are about o. i mm. long, and are peculiar 

 in that the accessory digit borne at the apex of the second segment is 

 longer than the third. The latter bears two small digits and a stout long 

 seta at its apex. Upon the basal segment are three small ocelli-like struc- 

 tures occurring commonly on most Chrysomelid larvae. They do not 

 seem to be the bases of broken set;«, but as to what they are or their func- 

 tion, I am ignorant. Possibly they are sensory pits. 



The labrum is irregularly rectangular in outline, and rather large, 

 being about .12 mm. broad. The anterior emargination common in all 

 the nearly related genera is indicated by markings, but has become 

 closed and almost obsolete. The setae are unusually stout. 



The mandibles of Chrysomelid larVcX are typically five-dentate, though 

 many variations occur, and many of the Eumolpin:>3 are entire. In Don- 

 acia only the two outer teeth are developed, the three inner ones being 

 represented by the serrated inner edge in D. crass ipes, though apparently 



A 



