L. D. Burling — Protichniies and Climactichnites. 397 



Conclusions. — The animals that inhabited tlie sea some 

 thirty million years ago are known to us with a perfection that 

 is a continual source of wonder, and the discoveries of the past 

 few years in these ancient rocks are little short of marvellous, 

 but that the Cambrian seas were peopled by a host of forms of 

 which we know little or nothing is no less certain than that the 

 waters of pre-Cambriaa time were full of life. While certain 

 of these unknown forms offer us nothing more substantial than 

 the record of their reptant efforts, the desire to know is responsi- 

 ble for attempts at their deciphering. The facts ai-e daily 

 becoming more numerous and the inferences surer. That Pro- 

 tichnites was made by a short, low-lying, and more or less 

 heavy set, approximately 12-legged crab-like animal, and 

 that Climactichnites w^as made by the snail-like creep of a 

 flexible slug-like animal which was frequently stranded at 

 low tide, but was able to swim in the waters of the full tide, 

 have passed the stage of guess-work and border on the real. 



LITERATUEE. 



1. Quart. Journ. Geol. Soc. London, vol. vii, pp. 250-253, 1851. 



2. Idem, vol. viii, p. 224, 1852. 



3. Canadian Nat. and Geol., vol. vii, pp. 276 and 277, 1862. 



4. Manual of Geology, 1863, p. 185. 



5. Quart. Journ. Geol. Soc. London, vol. xlvi, p. 599, 1890. 



6. Canadian Journ. Sci,, n. ser., vol. xv, p. 490, 1877. 



7. Quart. Journ. Geol. Soc. London, vol. xxvi, pp. 484-485, 1870. 



8. Proc. Amer. Acad. Sci., vol. xxxv, p. 403, 1900. 



9. Idem, vol. xxxvi, p. 61, 1900. 



10. Canadian Nat. and Geol., vol. vii, p. 276 and 277, 1862. 



11. Smithsonian Misc. Coll., vol. Ivii, p. 277, 1912. 



12. Smithsonian Misc. Coll., vol. Ivii, pis. 46 and 47, 1912. 



13. Idem, pis. 48 and 49. Many of the following observations are based 



on these plates. 



14. Canadian Nat. and Geol., vol. v, pp. 279-285, 1860. 



15. Bull. New York State Mus., No. 69, pp. 956-966, 1903. 



16. Smithsonian Misc. Coll., vol. Ivii, pp. 259-262, pis. 38-40, 1912. 



17. American Geol., vol. xxvii, p. 89, 1901. 



18. Canadian Nat. and Geol., vol. vii, pp. 274-277, 1862. 



19. Packard, Proc. Amer. Acad. Sci., vol. xxxvi, p. 66, 1900. 



20. Eastman, Textbook of Paleontology, 2d ed., 1913, p. 142 (noted by 



Dawson). 



21. The Geologist, London, vol. v, pp. 138-139, 1862. 



22. Principles of Stratigraphy, 1913, p. 1091. 



23. Manual of Geology, 1863, p. 185. 



24. Quart. Jour. Geol. Soc. London, vol. xxvi, p. 485, 1870. 



25. Proc. Amer. Acad. Sci., vol. xxxvi, p. 64, 1900. 



26. Trans. Wisconsin Acad. Sci., vol. v, pp. 276-281, 1882. 



27. 42d Ann. Kept. New York State Mus., 1888, p. 29. 



28. Science, n. ser., vol. xxviii, p. 382, 1908. 



29. Index Fossils, vol. ii, p. 248, 1910. 



30. Bull. New York State Mus., No. 69, p. 964, 1903. 



31. Textbook of Palaeontology, 2d ed., 1913, p. 142. 



32. Trans. Wisconsin Acad. Sci., vol. v, p. 277, 1882. 



83. Smithsonian Misc. Coll., vol. Ivii, pp. 259 and 260, 1912. 



