In a region like Panama, where blood-destroying diseases are so prevalent, the hemoglobin content of the blood and its variations are of special significance. The present work was undertaken in order to determine the relative effect on hemoglobin of certain conditions and infections. The results of the study will be discussed under the following heads :
I. The approximate normal hemoglobin of the colored man of the tropics.
II. The hemoglobin variation between natives of different West Indian islands furnishing the largest number of laborers for the work on the canal.
III. The relative frequency of infections.
IV. The influence of certain infections on hemoglobin.
V. The influence of climate, work and food on hemoglobin.
The tables given were constructed from hemoglobin estimations, by a uniform method, in 359 consecutive patients from the ranks of the colored male laborers of the Isthmian Canal Commission. The estima
tions were made on