684 Th. Fuchs, 



a kind of undulating seam or suture, the projecting portions of 

 one layer closing into corresponding depressions in the other. 

 These from being scarcely visible, become of considerable 

 magnitude, and the projecting portions on either side an inch 

 or more and even five or six inches in length. These have been 

 compared by M. Vanuxem to the sutures of the skull, 

 which the offen resemble. When separated, the surfaces 

 present a parallel fibrous or striated appearance, 

 and are frequently covered with a fibre of carbona- 

 ceous matter. These appearances, which occur not only in 

 this rock, but in the water lime and some of the higher rocks, 

 were termed by Prof. Eaton, Li gnilit e, from their resemblance 

 to Woody fibre. They are not always at the junction of 

 two layers, or as forming a division, but frequentl}^ 

 penetrate the solid Stratum, and are separable, ap- 

 pearing like wooden pin drivers into the mass. Again 

 they divide the rock into columnar blocks of variable dimen- 

 sions. The Illustration N° 32, is from a specimen where the 

 striated surface is eight inches long, and has separated a 

 portion of the rock into an irregulär column.« 



Die angeführte Zeichnung stellt einen grossen säulen- 

 förmigen Stylolithen dar. 



Auf Seite 130 und 131 beschreibt Hall ganz idente Er- 

 scheinungen aus Kalksteinen der Onondaga Salt Group. Er 

 bildet schöne Stylolithen und Drucksuturen ab und beschreibt 

 die letzteren folgendermassen: 



»The suture-like seams before spoken of usually occur 

 as horizontal lines of division, the striated surfaces 

 vertical. In the quarries at Mendon I observed some of these 

 sutures in a vertical position and the striated surfaces 

 parallel to the plane of stratification. These sutures 

 sometimes separate, presenting a surface covered with 

 toothlike projections«. 



»They will be readily recognized by any one after seeing 

 these illustrations, and since they are known to be widely 

 diffused and occurring in greater or less perfection in nearly 

 all the calcareous strata of the sj^stem, and even in the higher 

 rocks, they have become subjects of interest. The great lime- 



