ME. G. LEWIS ON JAPANESE LANGTJRIID^. 355 



rather less than the head at the region of the eyes ; eyes, viewed 

 from above, project clearly beyond the outline of the head; 

 thorax one third longer than broad ; legs one third longer than 

 in male, with only slight variation in the dilatation of the tarsi, 

 all approximate to those of the middle pair of legs in male. 



]Vote. The thorax of the female is much longer than in the male, 

 and a generic character is that the antennae are about as long as 

 the thorax. The female has therefore, what is unusual in Coleo- 

 ptera, longer antennae than the male; and there is apparently 

 some correlation between the length of the thorax and that of 

 the antennae. 



Mr. Bates possesses a species of this genus from Assam, and 

 I have another from the Andaman Islands. The described species, 

 D. victor, "White, and D. Whitii, Crotch, are from Madras and 

 Sumatra respectively". 



DOTJBLEDATA BTJCCULENTA, TV. Sp. (Plate XIV. figS. 1, 2, 3.) 

 Supra omnino obscuro-senea vel nigro-picea, subnitida ; antennis pecli- 

 busque nigris, thorace in medio profunde canaliculate, circa canaliculam 

 fortiter punctate, angulis posterioribus acutis, elytris fortiter punctato- 

 striatis, interstitiis perleviter corrugatis ; subtus nigra, abdoinine undique 

 punctato. Long. 12 ad 19 mill, c? capite latere sinistro valde angulato 

 (fig. 3), tliorace subquadrato, tarsis anticis dilatatissimis. 5 tliorace 

 latitudine longiore. 



Obscure brassy green, or more rarely pitchy black ; the head 

 and thorax at the sides have a few fine irregular punctures. The 

 thorax is canaliculate in the medial region, and this furrow is 

 occupied by larger and deeper punctures ; the posterior angles 

 are acute, and rather more produced in the male than in the 

 female. 



The curious sexual characters traced here are uniform and 

 generic. At first sight the enlargement of the left side of the 

 head in the male looks like a monstrosity; but it is merelv 

 another instance of that asymmetry which has been observed in 

 the mouth-organs of males of species in several families. One- 

 sided prognathism occurs also in Gallilanguria ^ , and in the 

 British Isles there is one instance of it in Agathidium rhinoceros. 

 I obtained this species in copula in Idzu in May 1880 and the 

 year following in Higo ; it is not common, and my series consists 

 of only twenty examples. The specimens were beaten off brush- 

 wood mixed with bamboo which overhung mountain rivulets in 

 well-shaded forests. This and the two following species are never 



