218 Professor Bonney — Plant-stems in Gneiss. 



disappointing. A truly clastic origin was constantly suggested, but 

 was not placed beyond dispute. Shortly afterwards we visited the 

 Museum at Berne, and again examined the famous stems. Pieces 

 had been cut from the ends, probably for the investigation undertaken 

 by Messrs. Von Fellenberg and Schmidt. One passed through the 

 longer stem, affording a crescentic section, and disclosed a third, 

 circular in outline and much smaller. I wrote thus in my diary : 

 " Both ' stems ' seem occupied by a material slightly darker, 

 greener, and compacter than the rest of the block. In places 

 there is about 0-1" or 0-15" of a phyllite-like substance, where 

 ' bark ' should be on the stem. The outer curve of the stem 

 appears not to enter the stone like a fracture would do, but more 

 as a fossil. The bark-like appearance is very conspicuous in the 

 upper, smaller, and ' indented ' stem on the face of the block. 

 This, neither in shape, nor in aught else, looks like a ' roll ' 

 in the rock. There are two or three surfaces of mechanical 

 division, but they do not appear to be the same, and the glaze on 

 them, which can also be traced in parts of the stem, seems a mere 

 film." After noting one or two other matters, I conclude thus : 

 " If plants, they are very rough and ill preserved ; but if the result 

 of mechanical movements, they are of a most extraordinary and 

 exceptional nature, and the rock certainly has the look of an 

 ' arkose ' rather than of a true gneiss." 



In the memoir before us Messrs. Von Fellenberg & Schmidt 

 give the results of the investigation which was no doubt in process 

 at the last-named date. It is illustrated by seven plates containing 

 nine figures, giving excellent representations of the supposed 

 remains, both as formerly visible and as disclosed by the new 

 sections. The latter are cut from both the upper and lower ends 

 of the longest stem, which, as we can observe in the photograph, 

 has an extraordinary resemblance to a plant. From a cross cut 

 the outline is seen in one case to be an oval, rudely flattened on 

 one side, in a second very rudely crescent-shaped, and in a third 

 nearly circular. The core of the enclosure, a very tough and 

 compact material, blackish green in colour, proves to be an 

 amphibolite ; for it is composed almost entirely of short columnar 

 grains of hornblende, between which lie allotrioraorphic water-clear 

 felspars, solitary scales of muscovite, zoisite in thread-like clusters, 

 and numerous grains of magnetite with jagged edges. The compact 

 exterior (the supposed bark) is described as practically composed 

 of biotite. Herr Schmidt has also examined the surrounding rock, 

 and maintains the accuracy of his description already published.' 

 In regard to the mineral constituents it agrees with what I have 

 seen in specimens believed to come from another part of the block, 

 especially with reference to the rather remarkable changes in texture, 

 though in my specimen the felspar is rather more converted to I 

 sericite, and the ' mortelstructur ' is less noteworthy or characteristic 

 than in the slices which he describes. The block is traversed by 



^ Loc. cit., p. 164. 



