1916] The Ottawa Naturalist. 49 



lime was originally deposited in lumps or masses. The lime 

 quite certainly came mainly from the decomposition of marine 

 algae in the manner lately described by Thomas C. Brown. 

 Without entering into a discussion of the questions as to what 

 plants and animals may have contributed to the limy deposit, 

 or in what manner the lime was collected, it is sufficiently evi- 

 dent to me that something deposited lime in small and large 

 masses. The lenses and lumpy patches of relatively pure lime 

 in all parts of the Galena-Trenton frequently inclose fossil shells, 

 etc., in a way to show that these limy bodies were soft when de- 

 posited; that is to say, they often partly inclose shells, stipes of 

 graptolites, fucoids, etc., either in the manner of objects over- 

 flowed by soft lime or in the manner of objects partly sunken into 

 such a soft deposit. Shells of Lingulae are found which had 

 bored into them and the boring, was done, of course, while 

 they were not consolidated." Sardeson himself advances a 

 rather ingenious hypothesis for the formation of "corrosion con- 

 glomerates" (op. cit. p. 276). He believes that the "fucoids" 

 found in the shaly limestones associated with the conglomerates 

 are the roots of a sea- weed, closely related to Camarocladia, and 

 that because of the hardness of the sea-floor these roots are 

 supposed to have been able to penetrate vertically but a short 

 distance, and thus could be easily uprooted by the rafting of 

 flotsam at the surface of the water. He concludes: "Since the 

 conglomerates are found in limited horizons instead of through- 

 out the beds or formations, their origin is to be attributed rather 

 to catastrophies, such as rafts of sea- weeds, etc., * * * *." 

 Here again we may have a true intraformational conglomerate 

 formed by vegetable means. 



Gleitungspheomene. 



Sub-aquatic and sub-aerial-gliding-deformation or soli- 

 fluction. Under the heading "Sub-aquatic, gliding deforma- 

 tion," Grabau (op. cit. p. 780) writes: "Offshore deposits of 

 sediments on a gently sloping sea or lake bottom may suffer, 

 from time to time, deformation of the surface layers through 

 gliding or slipping down the gently-inclined sea floor. * * * 

 The most remarkable fact about the gliding in Zug was that it 

 took place on an average grade of 6% (326'), while the larger 

 and more pronounced movement occurred on a grade as low 

 as 4.4% (231')). The material thus slid into the lake was 

 brecciated (italics are the author's) and folded with overfolds, 

 overthrusts, reversals of layers, excessive strata, etc., and fur- 

 nishes an excellent guide to the interpretation of similar move- 

 ment in the past." Under the heading "Examples of fossil 

 subaqueous solifluction," (op. cit. p. 781), the author quotes 



