VITACEAE 193 



5 inches long. Flowering occurs during the early part of July, 

 and the fruit, which hangs in loose or compact clusters 2 to 6 

 inches long, ripens about the first of October, The berries are 

 somewhat more than i/; inch in diameter, black, and without 

 bloom. Each contains 1 or 2 seeds, which may be globose or 

 hemispherical. 



Distribution. — The Catbird Grape grows in damp situa- 

 tions, such as the low ground bordering ponds and backwaters 

 of rivers, from Illinois to Iowa and south to Louisiana and 

 Texas. In Illinois, it follows the Wabash valley from Law- 

 rence County south to the Ohio River, around the state in 

 the Ohio and Cache River valleys, and northward along the 

 Mississippi to St. Clair County, 



VITIS RIPARIA Michaux 

 Riverbank Grape 



The Riverbank Grape, fig. 48, is a high-climbing, large vine 

 with shreddy bark and cordate, markedly acutely lobed, acute- 

 toothed leaves. The branchlets are smooth or sometimes 

 somewhat cobwebby, and the leaf blades, about as long as 

 wide, are 2 to 6 inches long, acute or acuminate at the apex, 

 and very broadly U-shaped at the base. Rarely the basal sinus 

 is so narrow that the basal lobes overlap. The margin is 

 densely ciliate and provided with 2 conspicuous lateral lobes 

 up to ^ inch long, which may point either forward or out- 

 ward. Their sinuses are acute. The teeth on the margins are 

 acute and each is tipped with a small short spine. The surface 

 of the leaf is smooth above, except on the main veins, and 

 more or less pubescent with whitish hair on all of the main 

 veins below. The petioles are one-third to two-thirds as long 

 as the leaf blade and more or less pubescent, especially on 

 the upper side. 



The inflorescence stands opposite a leaf and is 2 to 5 inches 

 long. The flowers open from the middle of May to about the 

 middle of June, and the fruit ripens during the latter part of 

 August. The fruit clusters are generally compact, rarely loose, 

 somewhat larger than the original inflorescence, and charac- 

 teristically provided with a large branch. The very sour, black, 

 densely bloom-covered berries are nearly 1/4 inch in diameter, 

 and each contains 1 to 4 seeds. 



