BEEKMANTOWN AND CHAZY FORMATIONS OF CHAM PLAIN BASIN 48 1 



Cameras shallow, about 8 mm distant in their middle portions 

 in the ephebic stage of the conch. Septa very concave, their 

 depth equal to that of two cameras. Sutures nearly straight 

 transverse, with but very slight indications of lateral lobes and hardly 

 any of the ventral saddles, while the dorsal saddles are more dis- 

 tinct. Living chamber incomplete in all specimens ; where most 



lgs. 39, 40, 41 D e 1 1 o c e r a s v a n i n g e n i sp. no v. Transverse sections at the begin- 

 ning of the living chamber; fig. 3g from the type (pi. 25), x y K ; fig. 40 from the specimen 

 reproduced on pi. 27, x X ; fig. 41 from that reproduced on pi. 28, x T 9 



perfect attaining the length of half a volution ; in the gerontic stage 

 becoming free in the best preserved specimens. 



Siphuncle large (about 8 mm just before the living chamber), 

 tubular, subventran in the last volution. Surface smooth, bearing 

 nothing but fine growth lines. 



Position and locality. One specimen each from beds B 8 , B, 

 and C- (Lower (/hazy) of the Yalcour section. 



