MM. Cole $f Holland— Structure of Rhobell Fawr. 447 



the Stiftkirche and commands a wide view over the Jurassic rocks 

 of Suabia, is the Museum that will ever remain as a monument to 

 the memory of the late Prof, von Quenstedt. The collection is a 

 most interesting one, and even Baedeker remarks that it "deserves 

 attention," though he only mentions the big 24-foot long Ichthyo- 

 saur, a fossil, however, which is dwarfed into insignificance by the 

 clump of 70-foot Crinoids. It is unnecessary to refer to the special 

 features of the Museum, as its contents may be summarized as the 

 collection of Prof. Quenstedt, including the majority of the originals 

 of the illustrations of his various works. To examine these every 

 student of Jurassic palaeontology must visit Tubingen, while the 

 physical geologist cannot fail to learn much from a study of this, 

 probably the best collection ever made to represent a fossil fauna. 



Heidelberg. 



Though there is little or nothing among either the Invertebrates 

 or Vertebrates that would induce a palaeontologist to visit Heidelberg, 

 he may well be excused if he turn aside to see the great petro- 

 graphical collection of Prof. Eosenbusch. Certainly, no geologist 

 who goes to Southern Germany should fail to examine it. The 

 collection illustrating rock metamorphism and the origin of the 

 crystalline schists is especially noteworthy ; all phases of this 

 controversy are illustrated, from the Norwegian mica-schists with 

 Trilobites' tails, to the disputed Nufenen Schiefer and the " spotted 

 rocks " of Scopi. 



Bonn. 



Like so many of the German Museums, that of Bonn has recently 

 changed its quarters. The collections have been moved from the 

 Poppelsdorf to the University, and they were still in the packing 

 cases at the time of my visit. Goldfuss's collection and the second 

 half of Sturtz's first series of Bundenbach Echinoderms are preserved 

 here. 



The stock of Herr Sturtz (No. 2, Biessestrasse) always contains 

 some novelties, and is well worthy of examination. 



In conclusion, it remains to again express my warmest thanks to 

 those whose unvarying courtesy and kindness rendered my visit to 

 the Museum > under their care as enjoyable as it was instructive. 



IV. — On the Structure and Stratigraphical Eelations of 



Ehobell Fawr. 



By Ghenville A. J. Cole, F.G.S., and 



Thomas H. Holland, A.N.S.S., Berkeley Fellow of the Owens College. 



IN a paper dealing with some phases of volcanic action in North 

 Wales, 1 it was urged that contemporaneous eruptive rocks 

 occurred on Cader Idris at lower horizons than the acknowledged 

 base of the Arenig, although the actual vents from which they had 

 arisen were lost and concealed under later accumulations. It was 



1 Cole and Jennings, "The Northern Slopes of Cader Idris," Q.J.G.S. vol. xlv. 

 (1S89J, p. 437. 



