I visited this locality several times during August and October, 1881. I found an abundance of the saline incrustation of which you have spoken, and at the time of my first visit there was a little pond hole just east of the point named that was in the act of drying up. Finally it dried completely up, and then the saline and green incrustations both were abundant enough. The only species, however, I found of the ague plants was the Gemiasma verdans. On two occasions of a visit with my pupils I demonstrated the presence of the plants in the nasal excretions from my nostrils. I had been sneezing somewhat. There is one circumstance I would like to mention here: that was, that when, for convenience' sake, my visits were made late in the day, I did not find the plants abundant, still could always get enough to demonstrate their presence; but when my visits were timed so as to come in the early morning, when the dew was on, there was no difficulty whatever in finding multitudes of beautiful and well developed plants. To my mind this is a conclusive corroboration of your own statements in which you speak of the plants bursting, and being dissipated by the heat of the summer sun, and the disseminated spores accumulating in aggregations so as to form the white incrustation in connection with saline bodies which you have so often pointed out. I also have repeated your experiments in relation to the collection of the mud, turf, sods, etc., and have known them to be carried many hundred miles off and identified. I have also found the little depressions caused by the tread of cattle affording a fine nidus for the plants. You have only to scrape the minutest point off with a needle or tooth pick to find an abundance by examination. I have not been able to explore many other sites, nor do I care, as I found all the materials I sought in the vicinity of New York. To this I must make one exception; I visited the Palisades last summer and examined the localities about Tarrytown. This is an elevated location, but I found no Gemiasmas. This is not equivalent to saying there were none there. Indeed, I have only given you a mere outline of my work in this direction, as I have made it a practice to examine the soil wherever I went, but as most of my observations have been conducted on non-malarious soils, and I did not find the plants, I have not thought it worth while to record all my observations of a negative character. I now come to an important part of the corroborative observations, to wit, the blood.