456 THE CANADIAN NATURALIST. [Yol. ix. 



that both the shells and the reptiles occurring in these trees must 

 have been strictly terrestrial in their habits, as they could not 

 have found admission to the erect trees unless the ground had 

 been sufficiently dry to allow several feet of the imbedded hollow 

 trunks to be free from water. In the highest of the three hori- 

 zons the shells occurred in an erect tree, but without any other 

 fossils, and they had apparently been washed in along with a 

 grayish mud.* 



2. Pupa Bigshii s. n. (Figs. 5 6.) 



Description, — Shell half the size of Fiip)a vetusta, or between 

 three and four millimeters in length, and one and five-tenths 

 millimeters in breadth. Form long, conical. Body whorl about 

 one-third of the entire length, giving the shell a somewhat 

 bulimoid form. Whorls five in the largest specimens found, 

 tumid, suture much impressed. Surface smooth. Aperture 

 apparently oval in form, but not perfectly known, as the body 

 whorl is crushed in all the specimens. 



A few specimens, none of them quite perfect, were found in 

 the erect trees of group XV at the Joggins, along with Fu2:>a 

 vetusta. They differ from that species in smaller size, different 

 form and absence of sculpture. The specimens do not show 

 whether the aperture was toothed or simple, but it was probably 

 the latter, as the lip is evidently very thin and delicate. From 

 its form it is probable that it belongs to a different sub-genus 

 from jP. vetusta. It is very much more rare than that species 

 in the erect trees, and has not been found elsewhere. 



I dedicate it to my venerable and dear friend Dr. Bigsby, 

 F.R.S., of London, a pioneer of American geology, and still an 

 indefatigable worker in the science. 



3. Pupa Vermilionensis Bradley. (Figs. 8 and 9, and 14c.) 



[Bradley in Report of Geological Survey of Illinois, vol. iv, p. 254 

 Id. in Am. .Jour. Sci., vol. iv, p. 87.] 



Descrip)tion .-\ — Shell spindle-shaped, tapering to an obtuse 

 apex, covered with microscopic ridges (25 to 30 in a millimeter) 

 parallel to the lines of growth. Aperture oblique, oval. Outer 

 lip thin, slightly reflexed. Columella lip reflexed, thickened ; 



* The discovery of the shells in this tree was made by Albert I. 

 Hill, C. E. 



t Slightly modified from Bradley. 



