Geological Society. 325 



great depth, in West Rosewarne Mine, Gwinear, Cornwall." By 

 H. C. Salmon, Esq., F.G.S. 



The boulders of granite referred to were found in the 50-fathom 

 level below the adit, the adit being 24 fathoms from the surface. 

 One of the boulders was 4 feet 2 inches, and another 3 feet 10 inches 

 in diameter ; there were five other smaller boulders or pebbles also 

 met with in the level. The boulders are in the killas close to the 

 lode, and both the lode and the " country " near the lode are made 

 up of brecciated killas. After quoting the details of somewhat 

 similar phenomena formerly observed at Relistian and Herland Mines, 

 the author treated of the probable origin of the boulders in question ; 

 and although lodes are regarded by some as having been formed from 

 below upwards, yet in this case the author thinks that the boulders 

 must have had a common origin with the lode, and have been intro- 

 duced by a fissure from the surface. 



2. " On an erect Sigillaria from the South Joggins, Nova Scotia." 

 By Dr. J. W. Dawson, F.G.S. 



This specimen, presenting the external markings of leaf-scars and 

 ribs with more than usual clearness and with some instructive pecu- 

 liarities, has afforded to the author the type of a new species, Sigil- 

 laria Broivnii. Observations on the probable mode of growth, on the 

 structure, and on the classification of Sigillaria, were also given in 

 this paper, together with a resume of the observations previously 

 published regarding Sigillaria by Brongniart, Corda, and others. 



3. " On a Carpolite from the Coal-formation of Cape Breton." 

 By Dr. J. W. Dawson, F.G.S. 



Numerous Trigonocarpa belonging to a new species (Trigonocarpum 

 Hookeri) occur in a thin calcareous layer in the coal-measures near 

 Port Hood, Cape Breton. The author thinks it highly probable that 

 though some Trigonocarpa may have belonged to Conifers, yet in this 

 case they were the seeds of Sigillaria. 



4. " On a Reconstructed Bed on the top of the Chalk." By W. 

 Whitaker, Esq., B.A., F.G.S. 



At some places near Reading (Maidenhatch Farm, about six miles 

 to the W.; and Tilehurst, two miles to the S.W.), and also near 

 Maidenhead, from 18 to 20 feet of broken chalk overlies the true 

 chalk ; and in places is overlain by the bottom-bed of the Reading 

 Beds, and therefore must have been reconstructed before the depo- 

 sition of the Tertiary strata. For the most part, however, in Berk- 

 shire the Woolwich and Reading Beds rest on an undisturbed surface 

 of the Chalk. In Wiltshire also the author has observed similarly 

 reconstructed chalk, probably there also underlying Tertiary beds ; 

 and he suggests that possibly the local reconstruction of the Chalk 

 may have been contemporaneous with the formation of the Thanet 

 Sands further to the east. 



5. " On some of the Higher Crustacea from the British Coal- 

 measures." By J. W. Salter, Esq., F.G.S. 



In this paper were described, (1) a new Macrurous Crustacean, 

 under the name of Antlirapalccmon Grossarti, from the slaty band of 

 the black-band ironstone of the coal-measures, Goodhock Hill, 



