86 NEW YORK STATE MUSEUM 



typically of transverse lines with short connecting cross-wrinkles 

 which may delevop into longitudinal lines. Conularia gra- 

 cilis from the upper Trenton shales, which already in its slightly 

 curved, slender form is very suggestive of relationship to Serpulites, 

 as representd byS. (Sphenoth alius) angustifolius, 

 shows how this Conularia-sculpture can be readily derived from 

 that of Serpulites. Its sculpture consists mainly of " sharply 

 undulating transverse striae " (Hall), which well compare with the 

 growth-lines or transverse wrinkles of Serpulites, and it can be 

 readily seen how the acute points of the angular wrinkles may 

 develop into the longitudinal lines. A further very important 

 connecting character is the composition of the tests in both Conu- 

 laria and Serpulites, of phosphate of calcium and chitinoid sub- 

 stance. Serpulites is typically sessile ; that also Conularia was 

 sessile, at least at times, is no more doubted. Besides the early 

 stages of Conularia gracilis showing fixation, Miss 

 Slater has also described a sessile Conularia 1 and the writer has 

 seen in the collection of Mr Frederick Braun of Brooklyn a large 

 slab with a number of large Conularias from the western Car- 

 boniferous, all of which are sessile, forming a radiating group. 

 Most Conularias, however, detached themselves later and must 

 have become free-swimming. If we finally add that the two 

 marginal thickenings of Serpulites are in structure comparable to 

 the thickened grooves of Conularia, it will be seen that there are 

 enough data to suggest that Conularia may well be a further 

 peculiar development of an annelid of the structure of Serpulites, 

 perhaps largely adapted to swimming. 



The following species of Serpulites are before the writer : 



i Serpulites interrogans nov. 

 Plate 29, figures 1 and 2 



The oldest Serpulites before us was collected by the writer in 

 the lowest zone of the Deep Kill graptolite shale (Tetragraptus 

 zone) and is of Beekmantown age. The tubes are small, about 20 

 mm long, slender and slowly expanding (from .5 mm to 1.7 mm+ 

 in length of 20 mm), strongly curved, smooth, very glossy, with 

 filiform marginal thickening and distinct, cup-shaped basal organs 

 of attachment. 



1 Ida L. Slater. A Monograph of British Conulariae. Pal. Soc. vol. for 

 1907. It is interesting that the authoress figures a number of cup-shaped 

 bodies, recalling those of Serpulites, about the center of the sessile C . 

 tenuis. 



