92 Reports & Proceedings — Geological Society of London. 



of sediments within it, and the continued operation of Charnian 

 movement, became converted into an anticline (as in the case of the 

 Wealden area). 



In an Appendix, Dr. Morley Davies discusses the interpretation 

 of the Saffron Walden boring, and its bearing on the supposed inter- 

 Charnian trough ; he also points out evidence of a post-Cretaceous 

 Charnian anticline under London. 



2. " Balston Expedition to Peru : Report on Graptolites collected 

 by Captain J. A. Douglas, R.E., F.G.S." By Charles Lapworth, 

 LL.D., M.Sc, F.R.S., F.G.S. 



The specimens of graptolites were collected from the rocks of the 

 Inambari district in Peru by Captain Douglas, under whose, name 

 the collection has been placed in the Geological Department of the 

 University Museum, Oxford. These fossils were forwarded by 

 Professor W. J. Sollas to Professor C. Lapworth, who embodied the 

 results of his study in a Report, of which the following is a brief 

 abstract. 



The specimens are recorded as all occurring in the same locality, 

 but it is not known whether they were obtained from a single zone. 

 The majority of the rock-specimens in which the graptolites occur 

 are black and somewhat pyritous carbonaceous shales, usually well 

 bedded and uncleaved, and the graptolites are in general well 

 preserved. The lithology of the containing rocks and the mode of 

 preservation of the graptolites are similar to those obtaining in the 

 richest graptolite-bearing strata of Britain, Europe, and North 

 America. 



The forms apparently represented in the collection are Logano- 

 graptus logani, Hall, a new species of Goniograptus (?), Didymograptus 

 stabilis, Elles & Wood, and D. hifidus, Hall, Phyllograptus angusti- 

 folius, Hall, Glossograpttis acanthus, Elles & "Wood, Cryptograptus 

 tricornis, Hall, var. Amplexograptus confertus, Lapworth, and 

 A. ccelatus, Lapworth. 



Taken as a whole this graptolite fauna may best be compared with 

 that of the Upper Arenig formation of Britain and its North American 

 equivalents, answering to the Lower Llanvirnian of Hicks & Marr, 

 and the Didymograptus hifidus zone of Elles & Wood and H.M. 

 Geological Survey. 



The assemblage of graptolites discovered in Bolivia a few years 

 ago by Dr. J. W. Evans corresponds very closely with this Peruvian 

 fauna, and was probably derived from the southward continuation 

 of the same Andean graptolite band. The Peruvian forms in the 

 Douglas Collection, like those from Bolivia, admit almost as close 

 a parallelism with those of the Arenig-Llandeilo graptolite beds of 

 Australia and New Zealand as with their representatives in the 

 Northern Hemisphere. 



Not only is the Douglas Collection of Peruvian graptolites 

 instructive and valuable from the palaaontological point of view, 

 owing to the number and good state of preservation of the species 

 represented, but it is of especial interest from the palfeographical 

 aspect, as affording additional proof of the identity (in general facies) 

 of the graptolite fauna of the sea-waters of Lower Ordovician times 



