304 MESSES. A. M. DAVIES AND J. W. GREGORY [Aug. 1 894, 



Brianconnais ' ; those of Zaccagua and Mattirolo, 1 who included 

 them in the Permian and Trias ; those of Gastaldi, 2 who regarded 

 the Calcaire du Brianconnais as made up of Lias, Trias, and Car- 

 boniferous ; or those of Kilian, 3 who regards this as composed of 

 Trias and Lower, Middle, and Upper Jurassic. 



One of us having failed on a previous occasion to find any trace 

 of the limestones on the pass of Mont Genevre, we commenced our 

 search on the eastern cliffs of the mountain. We struck up the Grand 

 Vallon, which cuts into the eastern face of Monte Chaberton ; we 

 climbed Mont Sisnieres and thence up the north-eastern crest to the 

 2620-metre stone man. About this point we found numerous fossili- 

 ferous boulders, some of which also occur near the entrance to the 

 Grand Vallon ; the beds from which we thought it probable that 

 these had fallen were inaccessible on this side. We therefore moved 

 to Bourg Mont Genevre and thence climbed Chaberton up the valley 

 of the Gr. Baisses. We could find only Triassic limestones on the 

 western slopes, but succeeded in discovering the coralline and shelly 

 limestones in situ on the north side of the valley of R. Clos des 

 Morts, just above a ruined sheepfold east of the Col de Chaberton. 

 (See Map, p. 309.) 



Pigs. 1 & 2 illustrate the mode of occurrence of these limestones ; 

 they are much contorted, and have been let down by faults into the 

 Triassic dolomites which are not especially crumpled. In places, as 

 shown in fig. 2, the shelly limestones are much contorted, and overlie 

 the uncontorted dolomites. There is therefore no doubt that the fossils 

 do not belong to the dolomite series, but to one of later date, and that 

 they have been preserved owing to their having been faulted down 

 into, or across on to, the Trias. As some name for these beds is 

 desirable, we propose to call them the ' Clos des Morts' Limestones. 



We made a considerable collection of the shelly limestones, bat 

 the fossils are so fragmentary that Mr. R. B. Newton, P.G.S., of 

 the Geological Department of the British Museum, is unable to deter- 

 mine any of them. We are none the less obliged to him for the care 

 with which he has examined the specimens. 



The corals, however, are more satisfactory : they all seem to 

 belong to one species, which we regard as the same as that found 

 by Michelotti in the Yalle della Vermanagna, on the northern side 

 of the Col di Tenda. This was identified as a Cyathophyllum.* 

 ]S"eumayr has pointed out the erroneous nature of this determina 

 tion, and sections made from specimens collected by us show that 

 it is one of the Astrceidce and belongs to the genus Calamophyllia. 

 As one of us has had recent occasion (in connexion with the Indian 



1 ' Sulla geologia delle Alpi occidentali,' Boll. R. Comit. geol. Ital. vol. xviii. 

 (1887) pi. xi. 



2 ' Sui rilevamenti geologici fatti nelle Alpi piemontesi durante la campagna 

 del 1877,' Atti R. Accad. Lincei. ser. 3, vol. ii. Mem. (1878) pt. ii. p. 959. 



3 ' Structure geologique des Chaines alpiues,' Bull. Soc. geol. France, ser. 3, 

 vol. xix. (1891) p. 615. 



4 B. Gastaldi, ' Su alcuni fossili paleozoici delle Alpi marittime e dell' 

 Apennino ligure studiati da Gr. Michelotti,' Atti R. Accad. Lincei, ser. 3, vol. i. 

 Mem. (1877) pt. i. pp. 122-123 & pi. i. 



