VI EEPORT OF NATIONAL MUSEUM, 1920. 



So that, when no extra help is available, the increase in material must 

 mean a decrease in the scientific output, and as it is by the quality 

 and quantity of the latter that the standing of an institution like the 

 National Museum is properly judged, and not by the numerical size 

 of the collections, an increase in the latter might be a handicap rather 

 than an advantage. However, with the increased accumulation of 

 specimens the scientific quality of the material must be supposed 

 to increase, as the gaps become less, and the series for comparison 

 larger, and in this respect, therefore, there is a distinct advantage 

 in the progressively greater increment of specimens. Moreover, it is 

 in the very nature of a growing museum that the collections should 

 continue to grow, as a stagnating museum certainly means a decay- 

 ing and retrograding institution. 



With these reservations in mind it is satisfactory to be able to 

 report that the total number of specimens received during the past 

 year amounted to 136,765. As compared with the 482,740 specimens 

 recorded for the previous year this has the appearance of a tremen- 

 dous decrease, but the latter unprecedented figure was due to the in- 

 corporation of a single private collection of mollusks consisting of 

 about 400,000 specimens, which it had taken the donor many years 

 to accumulate. Leaving this collection, therefore, out of our com- 

 parison it will be seen that, numerically the year 1919-20 was a very 

 prosperous one. 



An estimation of the scientific value of the increment is also sub- 

 ject to a reservation due to the unequalled importance of the mollus- 

 can collection alluded to above. But putting this aside, the reports 

 of the curators show a gratifying increase in the scientific importance 

 of the material received. While in some of the divisions the value 

 was at least equal to that of the previous year, in others the gain 

 has been so marked as to call forth special comment. This is particu- 

 larly true of the division of birds. No less than 163 species new to 

 the collection were among the bird accessions and no doubt a larger 

 number will be added when the two African and the Australian col- 

 lections are fully identified. This splendid result Avas particularly 

 due to the liberality of Mr. B. H. Swales, of Washington City, who 

 placed a fund at the disposition of the division by which it was 

 possible to obtain by purchase 96 species hitherto unrepresented in 

 the Museum, thus filling up many severely felt gaps in our series. 

 Mr. Swales has thus done for the bird collection what the Frances 

 Lea Chamberlain Fund annually accomplishes for the molluscan col- 

 lection. An equally gratifying report comes from the division of 

 insects to the eifect that the accessions of the present }^ear excel in 

 the unusual number of large foreign lots, especially as regards but- 

 terflies and moths, largely due to the activity of Mr. William Schaus. 



