KlTEDEMANN SESSILE CoNULAIM A. 



705 



duced in. Plate I, figure 4, and Plate 11, figure 1. The latter, which on 

 account of its general form, the structure of the four grooves and the 

 sculpture of the surface film, must he regarded as identical with, or very 

 closely related to C. gracilis, has a beautifully preserved cup of the same size 

 and structure as those attached to the original of Plate II, figure 2. 



5. Finally, it may be adduced as an additional argument for the 

 similarity of the observed appendages and the shell of a Qonularia, that in 

 some of the former (Cf. PI. I, fig. 1, c) a triangular subearbonaceous plate 

 is preserved which is strongly suggestive of the flattened apertural process 

 of the uppermost face. 



It is permissible to meet some of the objections which are easily sug- 

 gested in comparing the appendages with Cotiularia. There is first the 

 strangely curved form of many of the smaller and medium sized individuals. 

 As already stated, Hall's type, of about two inches in length, is "slightly 

 arcuate." The axes of the older specimens, however, which the writer pos- 

 sesses, as also the axis of the specimen figured in Plate II, figure 5, are 

 always perfectly straight. An examination of the shells of the young Con it - 

 laria establishes the fact that the better they are preserved the straighter 

 they are. (Cf. PI. I, figs. 1, 2.) Even some of the very smallest Oonu- 

 larim are straight. This, as well as an examination of such specimens (PI. I, 

 fig. 4), in which the youngest part only is bent and the older is perfectly 

 straight, leads to the conclusion that the young shells also of (J. gracilis w ere 

 straight, but probably more flexible than the more distal parts and perhaps 

 less able to resist the dissolving influence of the sea water. A group of fos- 

 sils (PI. II, fig. 7) which are attached to the poorly preserved cast of a 

 Trochoid ma shell, on account of the strong distortions of the wedge-shaped 

 appendages presents appearances differing most widely from those of Conu- 

 laria. In this case the appendages are identical with the leaves of Hall's 

 Splienothdllus angustifolius* The extensive destruction of the faces of the 

 pyramids in both specimens, as well as the very poor preservation of the gas- 

 tropod, is proof enough of the destructive influences t<> which they were 

 subjected and which may also have distorted the slender pyramids before 

 they were covered by sediment. On the other hand, both contain a sufficient 

 number of nearly straight shells (cf. especially Hairs figure) to warrant the 

 statement that the pyramids were originally straight. The writer's specimen 



* Palaeontology of New York, Vol. I, p. 261, Plate LXVIII, figure 1, 1H4T. Hall's type, wbichProfessor J. M. Clarke had the 

 kindness to lend the writer and which is figured on Plate IV, not only showB young individuals attached to older "leaves," but 

 also ring-like impressions of the basal cups and the transverse ridges of the grooves. The faces have left smooth impressions 

 only 



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