452 On Hemiptera Heteroptera from Japan. 



Length, $ (without appendages) 17, appendages 20 lines ; 

 ? 19, appendages 20 lines. 



According to Dr. Stal, who has seen the insect, it is allied 

 to his R. valida ; but, unfortunately, I do not possess a speci- 

 men wherewith to compare it and point out the differences. 

 In the shape of the metasternum it resembles R. chinensts, 

 Mayr, ' Reise der ost. Freg. Novara,' p. 191, t. v. fig. 59 b. 



Ranatra unicohr. 



Luteous. Crown between the eyes with a small callus. 

 Pronotum, anterior portion appearing as if thrust into the 

 posterior ; the latter finely dark-grey punctured, and its an- 

 terior margin above ^---shaped. Anterior thighs with a tri- 

 angular tooth beyond the middle. Anal appendages not two 

 thirds the length of the body. 



Head. — Eyes piceous or purplish brown, faintly shining. 



Thorax. — Pronotum, anterior portion pale brownish yellow, 

 stouter next the head than at its junction with the posterior 

 portion, into which latter it has the appearance of being thrust ; 

 posterior portion luteous, thickly and finely dark-grey punc- 

 tured ; its anterior margin above ww-shaped. Scutettum 

 brownish, with a small fovea on each side of the centre below 

 the middle. Elytra lurid, very thickly and very finely dark- 

 grey punctured. Membrane darker than the elytra, nerves 

 brown. Sternum lurid or somewhat testaceous. Legs luteous 

 or somewhat testaceous : thighs, first pair with a triangular 

 black tooth beyond the middle, second and third at the apex 

 narrowly brown : tibial lurid or yellowish ; second and third 

 pairs, especially towards the apex, on the sides with short, 

 spinose, black hairs ; apex narrowly dark brown : tarsi, second 

 and third pairs pale brownish yellow ; apex dark brown : 

 claws, second and third pairs at the base pale ; apex brown. 



Abdomen above pitchy brown, paler on the sides ; con- 

 nexivum luteous or pale brownish yellow : beneath lurid or 

 somewhat testaceous : anal appendages luteous. 



Length of body 13, appendages 7 lines. 



This is a genus of which I have seen and possess but few 

 species. All of those known to me are larger than the insect 

 above described, and which, although belonging to the group 

 with only one tooth in the middle of the anterior femora, has 

 as a distinguishing character short anal appendages. 



There are two male specimens in the collection. 



