December 7, 1900.] 



SCIENCE. 



quartzites, and a variety of volcanic rocks, 

 comprising andesites, rhyolites, dacites and 

 basalts. There were two periods of andesitic 

 eruption. The arkoses and the older ande- 

 sites which are among the most ancient rocks, 

 are cut by large dikes of tonalite, which have 

 altered the intruded rocks near the contact to 

 quartz, biotite, garnet and staurolite schists. 

 Strong, steeply dipping, jointing or sheeting is 

 one of the latest geologic structures, and ac- 

 cepting the principal uplift of the range as late 

 Pliocene, the jointing is probably not older. 

 Along these joints most of the ore deposits have 

 formed. The ores consist chiefly of arsenopy- 

 rite, chalcopyrite, phyrrhotite, pyrite, blende, 

 galena and some less important sulphides. 

 The deposits occur mainly in the tonalite and 

 to a leas extent in the older andesites, occasion- 

 ally in the other rocks. 



'The Mother Lode, folio, California,' by Mr. 

 F. L. Ransome. 



This special mining folio No. 63 of the Geo- 

 logic Atlas of the United States was shown and 

 its scope briefly outlined. It deals with an 

 area six and a half miles wide and seventy 

 miles long, embracing the greater portion of 

 the so-called ' Mother Lode ' system of gold- 

 quartz veins. 



' Paleobotanical Aspects of Some Upper Pal- 

 eozoic Formations of Nova Scotia,' by Mr. 

 David White. 



A brief rSsumS of the correlations by stratig- 

 raphy on the one hand with the correlations 

 by paleontology on the other hand. The Hor- 

 ton and the Riversdale plant beds, which are 

 referred by the Nova Scotia geologists to the 

 Hamilton, are, on the evidence of the fossil 

 plants, referable to two stages ; the Horton be- 

 ing Pocono and in the basal portion of the 

 lawn Carboniferous, while the Riversdale plants 

 indicate a stage for these at or near that of the 

 Pottsville. F. L. Ransomb, 



David White, 



Secretaries. 



NEW YORK ACADEMY OF SCIENCB8. 

 SECTION OF BIOLOGY. 



The regular monthly meeting November was 

 held on the evening of November 12th, Pro- 

 fessor C. L. Bristol, presiding. 



The following program was offered : 



F. C. Waite, ' The Bermuda Toad ' (to be published 

 in full in Science). 



H. F. Osborn, 'The Phylogeny of the EhinoceroaeB 

 of Europe.' 



H. L. Clark, ' Further Notes on Bermuda Echino- 

 derms.' 



Professor Osborn reported a continuation of 

 his investigations upon the ' Phylogeny of the 

 Rhinoceroses of Europe.' These animals ap- 

 pear to fall under the law of early divergence, 

 and to constitute at least six separate series or 

 phyla, which, so far as known at present, are not 

 genetically related to each other, but undergo 

 a more or less parallel development, as fol- 

 lows: Diceratheriiuse, Aceratheriinse, Brachypo- 

 dinse, Ceratorhinse, Atelodinse, RhinocerotinsB. 

 The chief criteria in distinguishing rhinoceroses 

 are the proportions of the skull, whether doli- 

 chocephalic or brachycephalic, the proportions 

 of the limbs in reference to cursorial or aquatic 

 habits, and the position of the horns ; subsidiary 

 to these features are the types of tooth struc- 

 ture. The origin of the Rhinoceroses is still 

 obscure, although it appears to be possible to 

 derive the Diceratheriinse from certain Eocene 

 Hydracodontidse. 



This study will be published in full in the 

 Bulletin of the American Museum of Natural 

 History, and it constitutes a part of the con- 

 tinuation of the author's memoir on the ex- 

 tinct Rhinoceroses. 



Mr. H. L. Clark's paper was read by Professor 

 C. L. Bristol. In this paper Mr. Clark gave 

 an account of the Echinoderms collected by the 

 party of zoologists from the New York Univer- 

 sity in the summer of 1899, together with a 

 summary of his own observations during April 

 of that year. It is to be concluded from an 

 abundance of observations that the distinctions 

 hitherto thought to exist between Stichopus 

 diaboli and acanthomela are not to be regarded 

 as valid, and the forms described under these 

 names must be referred to S. Mbbii. Twenty- 

 nine species are listed. 



Mr. Waite called attention to the fact that 

 the madreporio body in Asterias tenuispina 

 branches, forming 1-4 bodies in each animal, 

 thereby making orientation diflBcult. 



F. E. Lloyd, Secretary. 



