298 NEW YORK STATE MUSEUM 



are imbedded in the tissue of the plant. Scars showing where 

 other larvae have been feeding are representd at e and on plate 

 28, figure le. Several nearly mature larvae are shown on 

 plate 22;s attached to the underground stems. As the stem 

 elongates, new leaf stalks are formed at the growing end. 

 The bases of two of these are shown on plate 22a?. Just back of 

 these will be noted a number of rough, pitted, ovate areas 

 [pl.22?/], the leaf scars, the places where leaf stalks were 

 formerly attached. On many of these scars will be seen ovate,, 

 cylindrical bodies [pl.22o], which are the cocoons. The co- 

 coons are spun by the larvae from silk secreted by glands that 

 open in the mouth. When the cocoons are opened, larvae^ 

 prepupae, pupae, just transformed adults, or mature adults may 

 be found at the same time. On plate 22a are shown three co- 

 coons from which adults have emerged. 



^ The larvae are opaque white or slightly yellowish in color 

 and scarabaeoid in form. The head [pl.28, flg.l] is minute 

 and frequently almost concealed by the pronotum. The 

 eyes are present in p a 1 m a t a , though they are apparently 

 wanting in some other species. The labrum [pl.25, fig. 6] is 

 minute and usually four sided; projecting from its distal mar- 

 gin are a number of setae, the marginal setae [fig.Gmr/] which 

 are attached to its ental surface; its disk bears six long setae 

 arranged in pairs, a distal pair [fig.6(Zs], a median pair [fig.Omd] 

 and a proximal pair [fig.Gpa?] ; laterad of the discal setae 

 there is on either side a single long lateral seta [fig.G?s], and 

 near the discal setae there are one or two pairs of pitlike open- 

 ings, the sensory spots [fig.Gsw]. The thoracic segments are 

 rotund, with six short, hooked legs. The abdomen is composed 

 of 10 segments, seven of which are well developed, but the last 

 three are minute and curved beneath the sixth and seventh. 

 There seems to be considerable disagreement as to the number 

 of segments that are present. Ferris^ considers all that portion 

 beyond the seventh [pl-.27, fig. 17 and 19] as one segment, 

 Heeger that it is made up of two segments, while Schmidt- 

 Schwedt^ and Sanderson^ consider this portion to be made up 



iPeiTis, E. Histoire cles Metamorphoses dela Donacia sagit- 

 tal- i a e. Ann. Soc. Ent. Fr. (2) IMS. 6:33-48, pl.2, no. 2. 



-Schmidt-Schwedt, E. Nocb einmal uber der Athmung der Larven von 

 Donacia c r a s s i p e s. Berl. Ent. Zeit. 1889. 33:299. 



^Sanderson, E. D. Tlie larvae of Donacia p i s c a t r i x Lac, and 

 c r a s s i p e s Fab. Can. Ent. 1900. 32:252. 



