112 JOURNAL OF THE WASHINGTON ACADEMY OF SCIENCES VOL. 13, NO. 6 
Dr. C. L. Maruarr then proposed an alternative explanation of the occur- 
rence of the stumps. He exhibited an outline map taken from an old city 
map, from which it appeared that a stream called Slack Creek once flowed into 
Rock Creek from the vicinity of Dupont Circle, draining a large swamp to the 
north and east, and traversing the very spot where the excavation is now in 
progress. He therefore maintained that recent filling would account for all 
above the swamp layer, and this itself would date from the early white 
settlement of the District, about 260 years ago. He had been informed by 
one of the shovelmen that an old brick wall encountered in the digging was 
on the same level as the tree stumps. 
There was some discussion of the second theory, leading only to the con- 
clusion that much would depend on the existence of the supposed layer of 
clay 7 or 8 feet deep above the swamp and below the admitted recent fill. 
Dr. Maruatr had not detected this, but Mr. SrepHEenson had. 
L. O. Howarpn: Some informalities about pioneer workers in medical ento- 
mology (lantern). The speaker showed lantern slides of a large number of 
pioneer workers, giving interesting facts or anecdotes about each. 
C. W. Strives: Frequency of amoeba in man, and its significance in public 
health. In the war zone there was a great meeting place for men of all 
nations, and it was anticipated that returning soldiers might be infected with 
the amoeba of dysentery to an extent which might endanger the whole 
population. A conference was held in Washington to discuss the matter 
before the soldiers returned. It was thought from figures obtained by 
Kofoid that there would be from 400,000 to 700,000 cases of the disease 
among the returned men. An extensive examination of various classes of 
the population was carried out to get a basis for comparison. A circular 
was sent to all hospitals and medical schools, inquiring if an increase had been 
observecLin the disease as the men were returned. Only 4.5 per cent reported 
any increase. A total of 8029 persons in the general population were ex- 
amined, of whom 333 were infected, or 4 per cent; of 196 immigrants, 25 
per cent were infected; of 329 boys and girls in a school in the District of 
Columbia, 17 per cent; of 83 boys and girls in another school, between 8 and 
9 per cent; of 1547 civilians, 13 to 17 per cent; of 2984 ex-soldiers who had 
not gone to Europe, 8 to 9 per cent; of 3536 soldiers who had been in Europe, 
7.8 to 9 per cent; of 362 miscellaneous, 7-to 9 per cent. In these infected cases 
few showed symptoms of the disease, as they were evidently able to restore 
the infected tissue as rapidly as it was damaged. These were carriers rather 
than patients. A few years ago this distinction was not made, but now it is 
known to be of great importance. It appeared from the statistics collected 
that the returning men were no menace to the health of the country, as they 
_were less infected than the population at home. 
The disease is easily cured in early stages, but later on with much more 
difficulty, although a new remedy, a newly discovered drug, is able to reach 
the parasite in the lungs and liver, and promises to cure the chronic cases. 
J. M. Autpricu, Recording Secretary. 
644TH MEETING 
The 644th regular and 43d annual meeting of the Biological Society was 
held at the Cosmos Club December 9, 1922, with President Barry in the 
chair. 
The following 53 members were elected: JoserpH Becker, NORWELL BELT, 
R. A. Boauey, Jr., D. L. Brown, C. H. Carvin, Binuie Cass, R. G. Cone- 
pon, A. D. Daucuton, P. V. Dre Leon, W. S. Dretwiter, E. F. Ducry, 
= 
