212 TONICIA-FANNETTIA. 



lateral areas hardly elevated, irregularly rugulose. Mucro behind 

 the middle, much elevated. 



Inside having 10 slits in the anterior, 1 in the median, 14 in the 

 posterior valve ; teeth of the tail valve directed forward ; those of 

 the central and front valves sharper, deeply serrated outside and at 

 the edge. Sinus moderate, deep, flat, with about 20 delicate denti- 

 cles. Length 38, breadth 20 mill. 



Siquijor, Philippines. 



Chiton truncatus SOWB., P. Z. S. 1841, p. 61. REEVE, Conch. 

 Icon., 1. 16, f. 93.Acanthopleura f truncate GRAY, P. Z. S. 1847, p. 

 68. Tonicia truncata ADS., Genera i, p. 474, and of SHUTTLW. and 

 CPU. 



Resembles Tonicia (Fannettia) disjuncta in the partial separation 

 of the valves at the sutures. The tail-valve is formed much like 

 that of Acanthopleura. 



A variety with nearly smooth valves has been noted from Samar. 

 Carpenter described in MS. a Cumingian specimen as T. jugosulcata, 

 said to be from Tasmania, but he later regarded it as a form of 

 truncata. The locality Tasmania is very doubtful. 



Section Fannettia Dall, 1878. 



Tonicia * * , GRAY, P. Z. S. 1847, p. 67.Fannyia GRAY 

 Guide Moll. B. M., p. 185 (1856). Fannia CPR., not Fannia Rob- 

 ineau Desvoidy, 1830. Fannettia DALL, Proc. U. S. Nat. Mus. 

 1882, p. 284, 287, 289. 



This section is like Tonicia in all respects except that the mucro 

 is flattened, the teeth of insertion are somewhat longer, and the 

 broad girdle encroaches upon the valves at the sutures, nearly 

 separating them. 



T. DISJUNCTA Frembly. PI. 39, figs. 35-41. 



Shell oblong-ovate, reddish-brown, with green and straw-colored 

 markings; valves smooth, glossy, the anterior margins of the dorsal 

 valves are arcuate, the beak only of the next forward valve cover- 

 ing them, giving the valves a disjointed appearance. Lateral areas 

 low ; mucro of tail valve median, subplanate. 



Inside white; anterior valve having 9, central 1, posterior valve 

 9 short slits; teeth elongated and strongly grooved outside; 

 delicately serrated at the acute margins ; teeth of tail valve short 

 and solid behind, elongated in front. Eaves narrow; sinus dentic- 

 ulate. 



