14 Dr. F. M. Stapff—Crydalline Schids 



outcrops are known, and nothing more. From the same point of 

 view I also constructed (on the profile of the line of the tunnel) 

 two troughs and an intervening saddle in the Ursern valley, re- 

 marking (French text, p. 28; German, p. 26), "The saddles and 

 troughs drawn indicate no more tlian une maniere de representer the 

 course of the beds in the Ursern valley." The same remarks are 

 applicable to the general section on plate vi. of the geological map, 

 which represents an ideal connexion of repeated seams of dolomite, 

 calc-schists, and black and gray mica schists, between Val Piora 

 (Lago Cadagno) and Campolungo. I wish to say, that I am not 

 now satisfied with that profile, as it was not necessary to compress 

 the three or four beds between the Ticino valley and Campolungo 

 in a complicated system of folds, since they can quite as well be 

 representatives of diiferent horizons of a couple of beds repeated by 

 faulting. 



It must be admitted that the probability of faulting is, d priori, 

 greater than that of folding; this agrees with the mechanical con- 

 ditions of contraction as explained by the Rev. 0. Fisher in his 

 " Physics of the Earth's Crust," and a most demonstrative example 

 of this same view is shown in that part of the profile of the Gothard 

 tunnel which represents the central part of the massif. The up- 

 heaval of the mountain, the swelling, uplifting and overthrow of the 

 strata, are not so much due to wave-like folding of the crust, as to 

 its crushing and to the shoving and squeezing of the flakes over 

 and tlirough one another. 



IV. Organic remains in the Calcareous beds of the St. Gothard. — 

 Though 1 have not succeeded in finding crinoids at every spot in the 

 Ursern valley indicated on the geological map of von Fritsch, there 

 is no doubt of the existence of imperfect fi'agments of these 

 organisms in those and other places in the calcareous series of the 

 valley (see pi. iii. of the geological map of the railway line). 

 Cylindrical or elliptical sections of stems of crinoids or spines of 

 echinoderms, have been observed also in the tunnel ; for example, 

 in the gray cipoline. No. 43, at 2593 m., and in the black schist, 

 No. 46, at 2637 m., and in this latter undetermined fucoids were 

 also present. In addition to these, microscopic globules of coaly 

 matter and peculiar rod-like pyritic bodies, which in section resemble 

 some forms oi' for aminif era, have been noticed (black schist, No. 4.2, at 

 2582 m.). Some lamina3 of calcspar intersecting the crystalline 

 limestones and cipoline, were not infrequently covered with a net- 

 work of graphite (or other coaly material) so as to resemble organic 

 forms, but they are not organic, and have never been represented as 

 such by me (Geol. Durchsch. u. Tabellen, Nordseite, p. 54-59 ; text 

 to geol. profile, French, p. 23, 24; German, p. 21, 22). 



Only after a thorough examination of 26 slides taken from 

 different beds of the calcareous series between 2582 m. and 2783 m. 

 N. did 1 discover in two of them (No. 43 at 2593 m. and No. 45 

 at 2682 m.) traces of microscopic organic fragments,^ which I have 



1 Faint traces of structures, resembling those on No. 43, have also been lately 

 noticed in a section of No. 47. 



