274 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1923 



gotten, some have been modified in varying degree, some have been 

 confirmed and vindicated by subsequent discovery. 



The more intensive collecting of recent years, and especially the 

 technique devised by Hatcher and Wortman for the purpose of 

 preserving the whole of a fossil skull or skeleton, have brought in 

 year by year a larger proportion of complete specimens of fossil ver- 

 tebrates. The leading American museums are to-day peculiarly rich 

 in complete and well-preserved material, and the more progressive 

 museums of Europe have likewise adopted these methods, greatly to 

 the improvement of their collections. 



It is difficult to find any basis for a quantitative estimate of the in- 

 crease in our collections, or even of -a.ny particular portion of them. 

 So far as the American Museum collections go, the Cope collection, 

 gathered between 1872 and 1896, covers about 25 per cent of the 

 catalogue numbers, but is not in reality over 10 per cent of the collec- 

 tions in this department, as in former years many specimens were 

 separately catalogued that would not now be considered worth indi- 

 vidual record. The other 00 per cent was gathered during the last 30 

 years, and progressively more during the later decades. Perhaps it 

 would be fair to say that 20 per cent was gathered from 1892-1902, 

 30 per cent from 1902-1912, and 40 per cent from 1912-1922. Other 

 institutions would have proportions different from these. Probably 

 in Yale University or the National Museum the proportion of ma- 

 terial collected and prepared over 30 years ago would be higher ; on 

 the other hand, in the newer institutions all the material is relatively 

 recent. It is reasonable to regard the American Museum as fairly 

 representative in this matter and to conclude that, so far as American 

 collections go, nine-tenths of them have been obtained during the last 

 30 years and nearly half during the last 12 years. 



Progress in foreign museums has not been so rapid, especially in 

 Europe, where the earlier collections were more important and the 

 World War seriously curtailed, if it did not eliminate, all scientific 

 activities. Yet even in Europe large additions have been made since 

 the beginning of the century and some important ones within the 

 last decade. Judging from what I saw of the principal European 

 museums in 1900 and again two years ago, it would, perhaps, strike 

 a fair average to estimate that their collections have been nearly 

 doubled since 1900. 



I will try to specify the more important points in the progress of 

 the last 10 or 12 years. 



PALEOZOIC REPTILES, PERMIAN OF TEXAS AND SOUTH AFRICA 



On the origin of land vertebrates there is little to report in the 

 way of new discoveries, although the researches of Gregory and 

 Watson in respect to the relations of the earliest land vertebrates to 



