HERPETOLOGY OF JAPAN. 525 



Gray, Cat. Shield Rept. Brit. Mus., 1855, p. 65 (China). — Landemannia ? 



perocellata Gray, Proc. Zool. Sue. London, 1869, p. 216 (Formosa, 



Swinhoe, collector); 1873, pp. 53, 54 (fig. of mandibles). 

 1869. Landemania irrorata Gray, Proc. Zool. Soc. London, 1869, p. 216 (type- 

 locality, Shanghai, China; type in Brit. Mus.). 

 1880. Psilognathus lnvis Heude, Mem. Hist. Nat. Emp. Chinois, I, p. 24, pi. ii 



(type-locality, mountain and streams south of the town of Ning-kouo fou.) 

 1880. Temnognathits mordax Heude, M^m. Hist. Nat. Emp. Chinois, I, p. 26, 



pi. Ill (type-locality, environs of Shanghai). 

 1880. Gomphopelta officinx Heude, Mem. Hist. Nat. Emp. Chinois, I, p. 27, pl.iv 



(type-locality. River Houai, where it leaves the province Ho-nan). 

 1880. Ccelognathus novem-costatus Heude, Mem. Hist. Nat. Emp. Chinois, I, 



p. 29, pi. V (type-locality, eastern extremity of lake Tch'ao). 

 1880. Tortisterniim novem-costatum. Heude, Mem. Hist. Nat. Emp. Chinois, I, 



p. 31, pi. VI (type-locality, lake Tch'ao, department of Lu-tcheou). 

 1880. Ceramopelta latirostris Heude, Mem. Hist. Nat. Emp. Chinois, I, p. 33, 



pi. VII (type-locality, environs of Ngan-k'ing fou). 

 1880. Coptopelta septem-costata Heude, Mem. Nat. Hist. Emp. Chinois, I, p. 35, 



pi. VIII (type-locality, lakes of Tong-lieou (Ngan-houe). 

 1880. Cinctisternum bicinctum Heude, Mem. Hist. Nat. Emp. Chinois, I, p. 37, 



pi. IX (type-locality, irrigation ditches in the marsh of Ngan-k'ing). 



The interesting question as to the relationship of the individuals 

 with narrow or wide alveolar surfaces of the jaws, as illustrated by 

 Pere Heude's subdivision of the south Chinese species, can not be dis- 

 cussed here. It must be studied on the spot with proper regard to the 

 possibility of complications, due to local differentiations in the various 

 drainage systems as well as to the subsequent mixing of the latter 

 through irrigation canals. Boulenger has suggested '' a case of 

 dimorphism caused by a difference of diet," the fish-eating individuals 

 retaining the sharp beak of the young, while those feeding on mussels 

 with hard shells or on other hard substances are supposed to gradually 

 develop a broad crushing mandibular surface. He furthermore sup- 

 poses such individuals to interbreed, thus preventing the characters 

 from becoming permanent.*^ 



With regard to the identity of the Formosan and south Chinese 

 specimens and the related question of the distinctness of the latter I 

 refer to the discussion under A. japonica (pp. 517-519). 



Description. — Female, 4 years old; U.S.N.M. No. 34055; Tamsui 

 River, Formosa; March, 1903; A. Owston collection. Carapace short 

 ovate in outline; the anterior margin of the r?volute nuchal 

 border segmented toward the median line, a single tubercle on the 

 latter in front of the border; no median keel, nor lateral depres- 

 sion, the carapace descending evenly to both sides from the rounded 

 back; skin of carapace smooth, with about 24 longitudinal raised . 

 lines, which are entirely untuberculated, and nearh' all straight and 

 uninterrupted, except about three midway on each side, which are 

 wavy and occasionally interrupted; thes? lines terminate near the 



a Cat. Chel. Brit. Mus., 1889, pp. 242-244. 



