GEOLOGT. 325 



slate, at Derby, Vermont, on the cast shore of Lake Memphremagog, on 

 the Canada line. The granite, which was exceedingly characteristic and 

 typical, not only overlaid the limestone, but dipped down into it in veins, 

 which there (in the limestone) terminated. The limestone contains numerous 

 fossils. 



In reference to this communication of Prof. Hitchcock, Sir Wm. Logan 

 said he thought the granite had cut through the limestone, and it would be 

 readily inferred that when an intrusive rock cuts through a fossiliferous 

 rock, it might well overlie it. He conceived this granite to be of the same 

 age with the general formation of the granite in Maine. It was, in his view, 

 Devonian granite. He believed the limestone to be the same with the 

 beautiful Rutland marble, and was of the same age. 



Interesting Palaontological Discan-nj. During the past year, an exceedingly 

 perfect specimen of a fossil fish, of the genus Pteruspis, has been discovered 

 in the Lower Lndlow rocks, England. The position of these rocks is as- 

 signed by Mr. Murehison to higher beds of the Upper Silurian. Fish have 

 hitherto been found in the Upper Ludlow rocks, but none in the Lower 

 Ludlow, and consequently this discovery carries back the appearance of 

 fishes in the palaeozoic rocks to a period more remote than has before been 

 determined. 



At the Aberdeen meeting of the British Association, 1S")9, Mr. D. Page 

 stated that explorations made during the past summer, by Mr. Slimon and 

 Son, in the Upper Silurian formations of Scotland, had afforded ample indi- 

 cation of a very varied and curious crustacean fauna, altogether new to 

 Palaeontology. Molluscous remains of well-known Upper Silurian genera 

 had also been obtained in sufficient numbers to prove the affinities of the 

 beds; and indications of both an aquatic and terrestrial flora seemed by no 

 means rare throughout the strata. The specimens obtained had a threefold 

 value; first, as proving the true Upper Silurian epoch of the Nilberry strata, 

 and thus affording a clue to the investigations of other Sub-Devonian tracts 

 in Scotland, yet lint very imperfectly understood; secondly, as adding new 

 forms to the life of a former epoch, and thus extending the boundaries of 

 our zoological knowledge; and, thirdly, as enabling the Government palae- 

 ontologists, who had recently published their first monograph on the Enryp- 

 tericloe, to understand more clearly the nature of this curious family of Crus- 

 taceans, and to correct what must now evidently appear as misinterpretations 

 of their structure and affinities. In none of the beds explored had there 

 ever been detected any trace of fish-life. Sir R. I Murchison remarked that 

 language could scarcely exaggerate the value of Mr. Slimon's discoveries to 

 palaeontologists. 



Siib-Silurmn FossiJs. At a recent meeting of the Philadelphia Academy, 

 Dr. Leidy called attention to specimens of Palaeotroehus presented this even- 

 ing by Prof. E. Emmons, from Sub-Silurian strata, He stated that its or- 

 ganic nature had been denied by able authorities, but considered that its 

 symmetry and uniformity were in favor of its being a fossil. It had most 

 strongly the appearance of a coral. 



Dr. Le Conte had seen a similar body of larger size from the copper-bearing 

 rocks of Point Keewenaw, Lake Superior. He could not conceive that such 

 numbers of masses of similar form could arise from molecular action 

 forming concretions. 



Fossils from tlie Laurent inn Limestones. At the meeting of the American 

 Association, Springfield, 1859, Sir William Logan, of the Canada Survey, 



28 



