One of the best places I have ever found to get the sexes of Chrysops and Tabanus is in the tall grass that skirts the marshes of Sandusky Bay. This grass is the Phragmites of botanists and grows to a great height by July 1st. On July 6th, at Black Channel, when the wind was high I went into a patch of this grass that was so dense that I could not use a net to advantage. Here I saw an abundance of flies and found that by approaching them very slowly I could readily pick the specimens off with my fingers. The male and female of T. stygius, nivosus, C. æstuans and flavidus and the male of T. affinis and bicolor were taken in this way. I found that this same species of grass afforded excellent collecting wherever found, but most material was procured when the wind was high. On the same date and near the same place the male of C. flavidus was taken from the flowers of the common spatter-dock, and this and æstuans were procured by sweeping in the adjacent low-growing herbage. R. C. Osburn informs me that he has had excellent success in collecting Tabanids from tall grass near water in his experience. Tabanus sulcifrons Macq. is an abundant species in northern Ohio during the latter part of July and all of August. So common that by actual count twenty-eight specimens were taken from a cow in ten minutes, while a few that alighted on the animal during that time were not procured. August 1st of the present year I was at Hinckley, Medina County, and spent the day taking observations on this species. In the morning about nine o’clock I went to the border of a woods where I had often observed the species before. Here males and females were found in abundance crawling over the trunks and foliage of trees, on the fence along the woods and flying about generally. One pair was observed in copulation on the fence, and I am of the opinion that the presence of so many flies in the locality at the time is explained on the ground that it was the general mating place of the sexes. On several occasions I have made observations which lead me to believe that the sexes of various species of the family copulate among foliage often high up in the trees. As Tabanids are not easily procured with a net from the surface of a rough rail, I tried the experiment of picking the specimens off with my fingers and found that it was surprisingly successful, if the movement toward them was made very slowly until just ready to touch them when the fingers were gripped quickly. Near a watering trough where a herd of cattle drank daily I found males in numbers resting on the ground where the turf had been tramped off. Along Rocky River I observed both sexes fly down to the water and dip several times in succession and then away to alight on a stone on the bank or disappear from sight altogether.