198 TONKIA. 



of these differences however, do not avail to name specimen- in 

 which various characters of eZ^an* are combined with other char- 

 acters of cliilni.*!* ; so that while when typically developed the forms 

 may readily be separated, it is, I believe, impossible to classify 

 occasional synthetic specimens. I have therefore considered <-h if- 

 a phase or variety of d> </////*. 



Subspecies LINEOLATA Frembly. PL 41, figs. 25, 26, L'7. 



Shell oblong, moderately raised, the ridge rather rounded. Sur- 

 face smoothish. Ground color light fawn or fleshy, each valve 

 close/;/ and finely lineolate with chestnut, the lines concentric to the 

 umbones ; fifth valve marked with brown at the ridge, and often 

 some of the other valves are marked with dark brown or are entirely 

 of that color. 



L>il<i-af areas closely, finely granulated, and having two or three 

 rows of eyes extending down near the low, smooth diagonal. Central 

 areas smooth except for a group of engraved grooves on each side of 

 the smooth narron- (hr*al bawl. Second valve either smooth or hav- 

 ing a median carina. End valves granulate toward the periphery, 

 closely dotted with eyes in irregularly radiating rows. Urn bo of 

 tail valve anterior, the space in front of it smooth. ' 



Inside white, each valve marked with reddish under the beaks. 

 Sinus delicately denticulate. Anterior valve having 8-9, central 1, 

 posterior valve 9-10 slits; teeth blunt, pectinated. 



Girdle leathery, nude, yellowish-brown. 



Length 25, breadth 15 mill.; divergence 110. 



Length 40, breadth 23 mill. 



Valparaiso, Ch ill. 



Chit)i linfolatus FREMBLY, Zool. Journ. iii, p. L'i'4. suppl., pi. 17, 

 f. 7 (Good). SOWERBY, Conch. Illustr. (as syn. of elegant), f. 1 ">-l. 

 KI.KVK, Conch. Icon., t. 7, f. 34. Tmtinu Hn<>>i/afn$ CPU. 

 ? Chitm, bruguieri I'ot. & Mich. Galerie, i, p. 534 (1838.) 



The distinguishing characters of typical lineolatu." are the lack of 

 larger tubercles along the diagonal rid-v. and the fine concentric 

 line-painting. The characters of both sculpture and color-pattern 

 however, are in some specimens inextricably united with these of T. 

 elegan-, of which species I am therefore compelled to consider this a 

 variety. 



Many specimens show several valve- of uniform black-brown; 

 others are blotched on many valves with the same. The species 



