01 v. 



arras; the growth wrinkles, which mi the lateral U and 



prominent, are Weaker OD the central areas, the posterior part of 

 which appear sculptureless. The iimho seem.- to \v produced hack- 

 ward [heakedj in young shells, hut in this specimen it is so upon the 

 I'd valve only. The dorsal ridge is bluntly angular. The head 

 valve is long compared with its hreadth, the length of the front 

 slope equalling tliat of each of the posterior margins ; it shows weak 

 concentric sculpturing of stria?. Tlie tail-valve is small and narrow, 

 not much more than two-thirds as broad as the head valve, and also 

 notably shorter; its forward area is not shining; the posterior 

 segment is shining and sculptured like the head valve. 



The lateral areas and the outer anterior parts of the central areas 

 are yellowish-red with red marbling. The central area shows on 

 its middle part, a group of beautiful chocolate-brown and violet- 

 white stria?, radially diverging from the umbo. On the anterior 

 median valves are seen also a few clear brown streaks on the outer 

 part of the central areas. 



The single specimen before me is fastened on pasteboard, and 

 measures 13'5 by 6 mill.; the broadest valve is 5 mill., so that the 

 girdle is but *5 mill., wide. The third median valve of this specimen 

 is abnormal in being pure white. 



South Georgia. 



Chiton zschaui PFFR. in Moll. Siid-Georgien, Jahrb. Hamb. 

 Wissensch. Anstalten iii, p. 105, t. 3, f. 2 (1886.) 



This is placed in Tonicia with much doubt, for the presence of 

 eyes is not noted in Pfeffer's description, above. 



T. TEHUELCHUS d'Orbigny. PI. 40, figs. 13, 14, 15. 



Shell oblong, elevated, strongly carinated ; brown with two white 

 longitudinal zones ; head-valve and lateral areas radially sulcate- 

 bifurcate; central areas longitudinally punctate-silicate. 



Length 27 mill. (Orb.) 



Jj<n/ ii Sun lilni*, Patagonia* 



Chiton tehnelchus ORB., Voy. dans I'Amer. Merid., p. 488, t. i '.". 

 f. 7-13. 



The sculpture reminds one of Chcetopleura inlrn Wood. The 

 generic position is not certain. 



2. We*t I it'll' in species. 

 T. SCHKAMMI Shuttleworth. PI. 4:>, figs. r>4, 55, 56. 



Shell oblong, moderately elevated, roundly angular. Surface 

 polished. Qround-eolor l>uj)\ mnitlt<l, sp^-klcd <>r sometime* 



