OCIOBEE 18, 1895.] 



SCIENCE. 



499 



four are closely related to Coccosteus, and 

 belong to the same family. 



The set of casts exhibited in illustration 

 of the fossils has been prepared by their 

 discoverer, Dr. William Clark, and faith- 

 fully represents the originals, of many of 

 which only single specimens are yet known. 

 The labor of extricating them from the 

 pyritous shale has proved very heavy, and 

 much yet remains to be done in this direc- 

 tion. 



Professor W. B. Scott illustrated, with a 

 large number of slides, his paper on 'The 

 Tertiary Lacustrine Formations of Amer- 

 ica.' In Tertiary times one lake succeeded 

 another, giving an almost complete record 

 of that era in lacustrine deposits. Professor 

 Scott suggested the annexed correlation of 

 these deposits with the standard strata of 

 Europe: — 



9. Eqims beds Pleistocence. 



8 . Blanco formation Pliocene . 



7. Loup Fork beds Upper Miocene. 



6. John Day beds Lower Miocene. 



5. White Riverbeds Oligocene. 



4. Uinta beds. > / Paris Gypsum. 



3. Bridger beds. / _ i Parisien. 



2. Wasatch beds. ? ) Suessonien. 



1. Puerco beds. / I Cernaysien. 



A considerable break occurs between 3 

 and 4 and earth-movement then took place, 

 while a second hiatus is seen between 6 and 



7. 3, 5 and 7 are each divided into three 

 divisions, and the highest division of the 

 Loup Fork beds, the Palo Duro, may be 

 correlated with the basal Pliocene. The 

 Uinta beds were the evidence of the last 

 lake west of the Rocky Mountains ; the 

 lakes afterwards spread east to the great 

 plain. 



The paper by Mr. R. B. White, ' On the 

 Glacial Age in Tropical America,' described 

 a number of apparently glacial deposits in 

 the Republic of Colombia, almost under the 

 equator. He spoke of moraines forming 



veritable mountains, immense thicknesses 

 of boulder clay, breccias, cement beds, sands, 

 gravels and clays, beds of loess, valleys 

 scooped, grooved and terraced, monstrous 

 en-atics and traces of great avalanches. It 

 is a significant fact that over part of the 

 area the author supposes the ice period to 

 be contemporaneous with great volcanic 

 activity, so that the glaciers bore on their 

 surfaces little but loads of pumice, ash and 

 ejected blocks ; in other places, however, 

 the detritus appears to have been derived 

 from sedimentary rocks. The paper con- 

 cludes with some remarkable speculations 

 as to the cause of glacial periods. 



Dr. H. Woodward read an interesting 

 paper on some decapod crustaceans from 

 the Cretaceous formations of Vancouver Is- 

 land, in which he described four new species 

 from specimens sent him by Mr. J. F. 

 Whiteaves. These are named as follows : 

 Callianassa Whiteavesii, Palceocorystes Harveyi, 

 Plagiophthalmus f Vancouverensis and Homo- 

 lopsis f Eichardsoni. Some of these forms 

 approach very close to European Cretaceous 

 types. 



Turning now to the subject of palseon- 

 tology, a paper which is fraught with far- 

 reaching consequences in the near future, is 

 that entitled ' Notes on the Phylogeny of 

 the Graptolites,' by Professor H. A. Nichol- 

 son and Mr. J. E. Marr. 



The authors note that the number of 

 stipes possessed by graptolites has been 

 looked upon as a character of prime im- 

 portance, many genera being based on the 

 possession of a certain number. Again, the 

 ' angle of divergence ' has been looked upon 

 as an important factor in the diagnosis of 

 families. They are, however, led to believe 

 that a character of essential importance in 

 dealing with the classification of the grapto- 

 lites, and one which, in all probability, 

 indicates the true line of descent, is found 

 in the shape and structure of the hydro- 

 thecse, the point of next importance as indi- 



