186 Kansas Academy of Science. 



Dimensions of an average specimen : Length, 50 ; alt., 35 ; 

 diam., 16. 



The specimens obtained are very variable. So far they have 

 been found only at East Clallam in this region, and principally in 

 the lov^er horizon there. 



Miocene: Astoria, Ore. (Conrad). 



Oligocene-Miocene : East Clallam, Wash. (Arnold; Reagan). 



17. Tellina arctata, var. juana n., var. Plate I, fig. 17. 



Shell like lellina arctata Con., except ornamented with trans- 

 verse bands in addition to the faint, closely and regularly arranged 

 concentric lines shown on that species. 



Only a single specimen of this variety was obtained from the 

 lower series of the Oligocene-Miocene at East Clallam. 

 18. lellina clallamensis n. s. Plate II, fig. 18. 



Shell somewhat resembling Tellina hodegensis, but smaller and 

 thinner. 



Shell elongated, elliptical to narrow ovate, compressed, thin; 

 umbones anterior to center, pointed posteriorly; anterior portion 

 of shell almost evenly rounded; posterior dorsal margin slightly de- 

 pressed back of umbo; posterior extremity obliquely truncate, 

 straight from depressed margin back of umbo, front reflected; in- 

 ferior margin arcuate to almost straight in some specimens; cardi- 

 nal teeth not seen; pallial sinus long and thickened anteriorly (?) 

 (only a faint impression seen); anterior muscle-impression on 

 right valve large; ridge in front of impression extends nearly to 

 umbo; posterior muscle-impression in same valve is also sur- 

 rounded by a rather high ridge which extends nearly to the um- 

 bonal regions; the same is true of the muscle-impressions in the 

 left valve. A fragment of unworn shell shows the surface to be 

 marked with fine, regular, closely arranged concentric "impressed 

 lines. 



Dimensions: Lat., 35; alt., 21; from umbo to posterior extremity, 

 23; to anterior extremity, 20; length of anterior "muscle-ridge," 14. 



This shell can be distinguished from T. lodegensis by its being 

 smaller and thinner, by its umbones being placed anterior to center, 

 and by the thickened areas (ridges) on the inner-shell side of the 

 muscular impressions being larger, longer and extendiog farther 

 toward the umbonal region (a shell of a living T. hodegensis at 

 hand gives this ridge as only 8.5 and distant from the apex of umbo 

 11.5 at dorsal end). 



This is a very abundant species in the middle series at East 

 Clallam, and is Oligocene-Miocene in age. 



