292 



the woods: (i) high, comparatively level ground; (2) low, river- 

 bottom woods ; (3) slopes; and (4) ravine bottoms. A small, tem- 

 porary stream is in the south ravine. At the time that our field work 

 was started, trees covered the region quite evenly except in a few small 

 glades and about the west margin, where, over a few acres, consider- 

 able wood-cutting had been done. There was much diversity in the 

 height of trees, and a number of kinds were present. 



On the upland were chiefly oaks (Quercus) and hickories 

 (Carya), but walnut (Jiiglans), mulberry (Moms rubra), and su- 

 mac (Rhus glabra) were also present, as well as other species. On 

 the river bottom were maples (Acer), elms (Ulmiis), red oak (Quer- 

 cus rubra), wild cherry (Prunus serotiiia), coffee-tree (Gymnocladus 

 dioica), walnut, mulberry, bitternut hickory (Carya cordiformis), 

 and redbud (Cercis canadensis). Climbing plants, notably wild grape 

 (Vitis cinerea), >were common, especially in the low woods. Under- 

 growth was unequally developed ; in the upland woods in some places 

 the ground had little else than dead leaves and fallen twigs upon it 

 (see PI. LXXIII), while in other places, there were many bushes 

 (PI. LXXIV). Herbage was scant on the forest floor in the upland 

 woods but formed an abundant growth in the bottom woods (see 

 PI. LXXV). 



The little stream, which runs in an easterly direction, taking a 

 tortuous course through the south part of the woods, is an important 

 animal habitat; and it brings to the station a number of aquatic 

 vertebrates. For a good part of its course in the woods, it flows 

 through a ravine (PI. LXXVI). In the southeast corner of the 

 woods, however, it passes through a piece of low and level ground 

 where it is less shaded, and its banks have rank herbage. Farther 

 up stream, in the thicker woods, the banks have little low vegetation 

 on them and are covered chiefly with dead leaves, brush or other 

 forest debris. Figure i, Plate LXXVII, shows a part of the stream 

 in the lower, southeast corner of Bates woods. Throughout its 

 course, the stream is a series of clear, shallow pools connected by 

 narrow rills trickling over deposits of sand and gravel in the stream 

 bed. In the lower part of its course, east of Bates woods and on the 

 river flood-plain, the bed of the stream is ordinarily dry. Aquatic 

 plants, except some algae (chiefly Spirogyra, Oscillatoria, and dia- 

 toms) were absent. Water-striders (Gerris) and small crawfish 

 (Cainbarus) were the only invertebrates noted in conspicuous num- 

 bers by the writer. 



The country about Bates woods, which was an important factor 

 in determining the nature of its fauna, is rough and hilly. It was, 

 for the most part, originally forested, but now it is largely cleared 



