192 Mr. J. S. Baly on the differential characters 



Genus Ambrostoma, Motsch. 

 Schrenck. Reis. in Amurlande, ii. p. 208. 



Metasternum margine antico utrinqiie sulcato, apice 

 immarginato; ca3teris ut in Chrysomeld. 



Tlie single character given above, as separating this 

 genus fi'om Chrysomela,\'s, of more importance than would 

 at first sight a^Dpear. In Chrysomela and its allies the 

 apex of the metasternum is regularly margined for its 

 • whole extent. In Doryyhora, Calligrajjlia, and all the 

 other American forms (one or two small genera excepted), 

 the anterior margin is bordered within, on either side, by 

 a deep sulcation, the apex itself being immarginate ; this 

 form of margination is found in the present genus and 

 also in Eumela, Paralina, and some Australian genera, 

 showing their closer connection with what may be called 

 the American type than Avith the European. 



1. Ambrostoma quadri-impressa, Motsch. Bull. Mosc. 



1845, i. p. 109; Schrenck. Reis. ii. 1860, p. 227, 

 tab. 11, f. 11. 

 Hab. — Mongolia. 



2. Ambrostoma fortunei, Baly, Journ. Ent. i. 1860, p. 94 



( Clirysomela). 



A. chinensis, Motsch. Schrenck. Reis. ii. 1860, 

 p. 228. 

 Hab. — Northern China. 



3. Ambrostoma mahesa, Hope, Gray, Zool. Misc. 1831, 



p. 30 (^Chrysomela, type in Brit. Mus.). 



A. nejKilensis, Motsch. Schrenck. licis. ii. 1860, 

 p. 228. 

 //a^.— Nepal. 



Genus Ceosita, Motsch. 



Schrenck. Reisen. ii. p. 189. 



Corpus ovatum, apterum aut alatum. Thorax lateribus 

 incrassato-marginatis. Elytra coadnata aut libera. Meta- 

 sternum apice elevato-marginatum. Pedes, tarsorum arti- 

 culis subtus glabris, nitidis, utrinque serie unica e setulis 

 I'igidis marginatis; articulo secundo apice concavo, angulis 

 acutis ; tertio profunde concavo-cmarginata, lobis acutis ; 



