88 NEW YORK STATE MUSEUM 



This is the species which has afforded in three specimens the 

 chitinoid setae within the apertures of the tubes. It was of a 

 gregarious habit, for in one instance three specimens with their 

 disks in contact are attached to one small fragment, and in another 

 (pi. 28, fig. 5) a dozen specimens are counted upon a small 

 pile of debris of brachiopod and cephalopod shells, which in the 

 soft mud formed a base for attachment. 



The species occurs in the upper Canajoharie (Dolgeville) shale 

 at Dolgeville and the Utica shale at Holland Patent. 



6 Serpulites magnus nov. 

 Plate 28, figures 1 and 2 



During the construction of sewers in the village of Menands 

 north of Albany some years ago, several blocks of much contorted 

 Canajoharie shale were obtained by Doctor Clarke which are 

 literally filled with extremely glossy thick tubes of the structure 

 of Serpulites. The tubes are quite uniformly 7 to 8 mm wide and 

 since none of the specimens show any trace of tapering to either 

 end they must have been of considerable length ; they are all 

 fragments limited by the size of the blocks (70 mm in maximo) . 

 The marginal welt is very thick (1.5 mm wide) and appears fre- 

 quently in the middle line of the flattened specimens as a carinate 

 ridge. The test is mostly smooth, but exhibits in some cases regular 

 transverse lines with smaller connecting longitudinal wrinkles. It 

 is possible that the appearance of perforation of the rock in all 

 directions is due to the contorted condition of the rock, as for 

 the most part the specimens follow the bedding planes of the shale. 



This species must have borne some resemblance to S . d i s s o - 

 1 u t u s Billings from the Trenton of Ottawa, etc., which attained 

 a like width, but judging from the original description, tapered more 

 rapidly and was altogether shorter. 



7 Serpulites tener nov. 

 Plate 28, figures 3 and 4 



A fragment of a Serpulites-tube 46 mm long and 1 to 2 mm 

 wide attests the occurrence of the genus in the Hamilton shales. 

 It comes from the top layers of a bluestone quarry near Clarksville, 

 N. Y., on the road between Mud Hollow and Reidville. 



The marginal welt is well developed, the test very thick and 

 smooth and furnished with deep, regular, elliptic depressions on 

 the median. line. The fragment shows no tapering toward either 

 end and the species must have been an extremely slender and long 

 one. 



