232 



rather few and usually simple, 4-10 cm. long, those of the trunk branched, 

 spines do not develop on the year's growth; leaves from old wood pin- 

 nate, from the year's growth bipinnate; rachis grooved and pubescent 

 or puberulent above and smooth below; leaflets generally 7-11 pairs, 

 variable in shape and size, generally lanceolate and 1.5-2.5 cm. long, on 

 petiolules about 1 mm. long, glabrous; flowers similar to the preceding 

 species; fruit a glabrous, shining, oblique pod about 4-5 cm. long, con- 

 taining 1 seed; seeds orbicular, flat, chestnut brown, about 1 cm. in 

 diameter. 



Distribution. Atlantic Coast from North Carolina south to 

 Florida, and the Mississippi Valley from southwestern Indiana south- 

 ward to Texas. In Indiana this species is rare and limited to the banks 

 of river sloughs, locally called ponds and to one cypress swamp. It is 

 known to have occurred on the banks of Wabash and Dan's ponds and 

 Little Cypress swamp in the southwest corner of Knox County, and in 

 Gibson County on the bank of a slough near Skelton and about Bur- 

 nett's pond. The reference to Posey County is without a verifying 

 specimen, although it may be found in the county. The writer has 

 visited about every place in the county where the species might occur, 

 and has never found it. Gorby's 1 reference for Miami County is with- 

 out doubt an error. In our area it is a low crooked tree and grows with 

 its base submerged more or less during the year. The idea of the pro- 

 portions of this tree can be obtained from the measurements taken from 

 the largest tree now known in Indiana, which is located on the shore of 

 Dan's pond in Knox County. It measures 158 cm. (66 inches) in cir- 

 cumference at 1 m. above the ground, and is estimated to be 10 m. (30 

 feet) high. This species is too rare to be of economic importance. 



Gleditsia aquatica x triacanthos. Dr. Schneck 2 found two honey 

 locust trees which he described as hybrids of the two species. The one 

 was located on the bank of Dan's pond in Knox County, and the other 

 in Gibson County. The original description is as follows: "In both 

 instances the pods are the distinguishing feature. These are very 

 much alike in both trees, being about 5 inches long, 1^ inches wide, 

 smooth, shining, of a light brown color and entirely destitute of pulp. 

 Otherwise the tree cannot be distinguished from the trees among 

 which they stand. They are both about 50 feet high, with short 

 stems and spreading branches, and stand about 5 miles apart." The 

 writer has five fruiting specimens from these two trees, taken by Dr. 

 Schneck. Two of the sheets have the round and branched spine^ of 

 G. triacanthos. 



ilnd. Geol. Kept. 16:169:1889. 

 2 Plant World 7:252:1904. 



