192 MR. M. JACOBY ON NEW [Feb. 17, 



single hair ; surface closely, irregularly, and finely transversely 

 wrinkled or ruzose througliout ; another similar tubercle like the 

 anterior one, also furnislied with a single seta, is placed at the posterior 

 angles. Scutellum triangular, pubescent. Elytra distinctly narrowed 

 behind, truncate at the apex, their surface flattened, with a generally 

 distinct oblique depression from the shoulder to the suture, strongly 

 punctate-striate to the apex ; the interstices everywhere transversely 

 wrinkled, but more strongly so towards the base. Legs slender, the 

 posterior femora not quite extending to the apex of the elytra and 

 furnished with a short acute tooth. 



The female is often much larger and especially broader, being 

 sometimes of double the width of the male, and proportionally 

 more robust ; the elytra are also more strongly wrinkled as well as 

 the thorax, and the antennae slightly shorter. 



Junsai. 



Of this species manv specimens were obtained living on a kind 

 of water-lily, and although closely allied to several European and 

 North-American forms, I am unable to identify it with any of 

 them. The nearest allied amongst the European Donacias seems 

 to be 2). aquatica, L. This species is, however, broader, less 

 elongate and narrowed behind, the colour of the elytra is quite 

 different, and their punctuation much finer and less deep ; the 

 basilar oblique depression is also much less distinct. The thirteen 

 specimens before me of D. gracilipes show no variation whatever 

 except in size, and the species may be principally known by the 

 nearly square-shaped thorax, and its short, but acutely produced 

 anterior and (to a less extent) posterior angles in connection with 

 the oblique anterior elytral depression, and the slender third and 

 fourth joints of the antennae. 



DoNACiA coNSTRicTicoLLis, sp. nov. (Plate XI. fig. 2.) 



Robust, convex, obscure cupreous or brownish seneous ; antennae 

 and legs ferruginous ; thorax much narrowed behind, shining and 

 finely punctured ; elytra with a basilar depression, strongly punctate- 

 striate ; the interstices transversely wrinkled ; posterior femora with 

 a broad tooth. 



Length 4-4|- lines. 



Head closely pubescent, with a central impressed longitudinal line. 

 Labrum and jaws fulvous. Third and fourth joints of the antennae 

 equal ; the three or four terminal ones fuscous or stained at their 

 extremities only with that colour. Thorax longer than broad, 

 greatly narrowed near the base; the sides near the anterior angles 

 strongly produced into a broad callus, below the latter less swollen ; 

 surface covered with fine punctures, which are a little more closely 

 placed and slightly confluent in the female near the anterior and 

 posterior margin ; the latter with a shallow transverse groove ; rest 

 of the surface smooth and very shining. Apex of the elytra rounded. 

 Femora robust, the posterior ones dilated into a broad triangular 

 tooth. Abdomen tinged with rufous. 



Lake at Junsai. 



