NO. 1985. NEW SPECIES OF SILURIAN FOSSILS— WILLIAMS. 323 



Genus CHONETES Fischer de Waldheim. 



CHONETES EDMUNDSI, new species. 



Plate 29, figs. 6, 7, 8, 9. 



Description. — The typical characters may be defined as follows, 

 namely: Size, small, rarely wider than 12 mm. and generally less 

 than twice as wide as long; pedicle valves convex, arching up from 

 the cardinal border abruptly at the umbonal region, and flattened 

 at the cardinal angles; body of shell swollen; brachial valve flat- 

 tened, concave; radii occasionally bifurcating, but over body of 

 shell radii simple to near front; radii on the ears near the cardinal 

 border much finer and fainter than over body; 60 to 90 radii can 

 be counted at >the margin, the larger total number due mainly to 

 increase m the number of fine radii on the flattened cardinal angles; 

 spines four on each side of the beak, the outer ones larger than the 

 mner; in an occasional large specimen five spines have been counted. 



Formation and locality. — Edmunds formation: Calcareous shales 

 about one-half mile south of Field Point on west shore Cobscook 

 Eiver (loc. No. 8.21. lA) ; west side of Burnt Cove (loc. No. 5.51. 5A) ; 

 Field Pomt (loc. No. 8.1.8A) ; extreme northwest comer of cove, near 

 outlet of Roaring Lake, southern part of Edmunds (loc. No. 7.42.6A), 

 all in Edmunds Township, Washington County, Maine. 



Cotypes.—Cat. Nos. 58945, 58946, U.S.N.M. 



Comments. — Chonetes edmundsiWillioias. In the fauna of 5.51.5A 

 is found a Chonetes which presents some of the features of C. 

 striatella, but is distinctly smaller. Only four specimens have been 

 seen (Nos. M1483. 1,2,3 and M1158). 



Specimen No. Ml 158 is the mold of the exterior of a pedicle valve 

 the front edge of which is wanting, so that the length is estimated. 

 Dimensions are 10 by 6 mm. The umbo is not elevated and the 

 convexity of the umbonal region is shght. There appear to be 

 4 spines each side the middle, which in the specimen appear to be 

 short. The ears are flattened, and on them the radii occasionally 

 bifurcate and are about 40 at the margin. 



Specimen No. M1483.1 is the exfoliated mold of, probably, a 

 pedicle valve; the spines on the cardinal margin are indistinct, but 

 faint traces of 3 of the 4 are evident on the left side. The beak is 

 not projecting, and the umbonal region at the margin is little elevated, 

 but the central part of the shell is roundly swollen and the ears flat- 

 tened. The radii are about 40 at the margin, and they occasionally 

 dichtomise in growth. Dimensions are 1^ by nearly 7 mm. 



Specimen No. Ml 483. 2 is a partly exfoliated pedicle valve, without 

 any trace of the spines visible, and the portion of shell present appears 

 to be perforated by some borings and is smooth. This may be the 



