Carboniferous Fossils from Siamn. 173 



perfect example agrees with Kayser's fig. 4 of the same species. 

 Bather ^ has described and figured this species from the Lower Culm 

 Measures of Devonshire, and it seems to be characteristic of the 

 Lower Carboniferous. 



Productus IcBvipunctatus Sarres. (PI. II, Fig. 14.) 

 One small internal cast of a nearly complete but slightly 

 distorted pedicle-valve, with the brachial-valve displaced but 

 attached, appears to be indistinguishable from the, shell figured 

 by Kayser '■^ as Productus Icevipunctatus Sarres. Our specimen is 

 not crushed, and the shape of the pedicle-valve and large incurved 

 beak are well seen. The species occurs typically in the Culm of 

 the Continent. 



Productus cf. plicatus Sarres. 

 The imj)ression of part of a brachial-valve of a species of 

 Productus showing the ornamentation may be compared with 

 Pr. plicatus Sarres,* which occurs in the Culm of the Continent, 

 and probably also in the Lower Culm of Devonshire.^ 



Clionetes cf. rectispina Von Koenen. (PI. II, Fig. 15.) 

 In one of the specimens of a small species of Choyietes, the cardinal 

 spines are preserved, and there are four on each side of the beak, 

 successively increasing in length outwards, and all are directed nearly 

 at right angles to the hinge-line. The shell itself is semi-elliptical 

 to semicircular, and the cardinal angles are rectangular. The surface 

 is not well preserved, but seems to have been covered with close, 

 fine, radiating lines. In its characters, so far as known, it resembles 

 Ch. jyerlata (McCoy),^but more especially C/*.reciwj9ma Von Koenen,® 

 from the Culm of Germany and Barnstaple.'' Ch. joseudovariolata 

 Nikitin,*' which is figured by Loczy ^ and Schellwien ^° from the 

 Carboniferous of China, possesses the same general shape and 

 ornament, but the cardinal spines are rather obliquely directed 

 outwards. Our best specimen from Siam measures 6 mm. in length 

 and 9'5 mm. in width. 



^ Bather, Quart. Journ. Geol. Soc, vol. li, 1895, p. 650, pi. xxviii, figs. 9, 

 9a, 96. 



2 Kayser, Jahrb. preuss. geol. Landesanst., 1882 (for 1881), p. 80, t. iii, fig. 5. 



^ Kayser, ibid., p. 81, t. iii, figs. 1, 2 ; Leyh, Zeitschr. chut. geol. Gesell., 

 xlix, 1897, p. 540. 



^ Bather, Quart. Journ. Geol. Soc, vol. li, 1895, p. 649, pi. xxviii, figs. 10. 

 10a, 106. 



5 McCoy, Syn. Carb. Foss. Irel, 1844, p. 120, pi. xx, fig. 9. 



® Von Koenen, Neues Jahrb. f. Min. Geol., 1879, p. 327, t. vii, figs. 4a, 46. 

 Kayser, Jahrb. k. preuss. geol. Landesanst., 1882 (for 1881), p. 78, t. iii, figs. 

 13, 14. 



^ Bather, Quart. Journ. Geol. Soc., vol. li, 1895, p. 650, pi. xxviii, figs. 12, 

 12a, 126. 



s Mkitin, Dep. Garb. Moscou, Mem. Com. Geol. Russ., vol. v. No. 5, 1890, 

 p. 27, t. ii, figs. 1-4. 



" Loczy, op. cit., p. 73, pi. iii, figs. 8-13. 



^° Schellwien, in Futterer's Durch Asien, Bd. iii. Lief, i, 1903, p. 142, t. i, 

 figs. 5-8. 



