EXGELMANN — NORTH AM. SPECIES OP JDNCDS. 497 



Bigelow ; 35 South Carolina, Ravenel ; var. biflorus is a 

 stouter plant with broader leaves, rough on the edges and a 

 larger panicle; Hb. n. 38 Delaware, Commons ; 39 S. Caro- 

 lina, Ravenel. Intermediate forms do not seem to be rare 

 and are found in Hb. n. 36 and 37. Characters taken from 

 the relative length of the inner and outer sepals, or from the 

 differences in the shape of the capsule, seem to be entirely 

 inconstant. No species bears more abundant seed than this, 

 but in the collections it is rarely found fully mature. 



Pag. 455. J. pelocarpus ; as far west as the banks of the 

 St. Peters river, in Minnesota, C. C. Parry.— It seems that 

 the plant attains its normal development, and bears fruit only 

 in a northern climate, and grows then only 4-7 or 8 inches 

 high, Massachusetts, Tuckerman in Hb. n. 45, while the pro- 

 liferous forms usually become 1 or 2 feet high, New Jersey, 

 Smith & Leidy in Hb. n. 46; the interesting southern var. 

 crassicaudex, Florida, Chapman, Hb. n. 47, is often 2 feet or 

 more in height and bears a very large decompound panicle, 

 5-9 and even 11 inches long. 



A specimen of Michaux's J. fluitans, from his own her- 

 barium in Paris, bears me fully out in my supposition that it 

 is a depauperate water or mud form of this species ; its short, 

 rooting stems, about 4 inches long, bear single terminal 2- 

 flowered heads; the flower I could examine was not fully 

 open yet, and leaves me in doubt whether it is 3- or 6-an- 

 drous. The description of La Harpe is not quite correct in so 

 far as he attributes to the head 2 external bracts; while they 

 have 3 as the 2-flowered heads of the regular form have, one 

 under each flower, and a third one above the upper flower. 

 Michaux found his plant, as Prof. O. Brunet of Quebec in- 

 forms me, on the Chicoutimi, about 100 miles north of Quebec. 



Pag. 458. J. articidatus, as far west as the shores of Lake 

 Erie,^?. W. Clinton; in Herb. norm. 48 from Western New 

 York, Sarticell, and 49 from Massachusetts, Tuckerman.— A 

 form with obtuse 5-flowered green heads in a spreading and 

 often almost level-topped panicle, obtuse, mucronate sepals 

 and obtuse short mucronate capsule, which I designate as 

 var. obtusatus, has been found by Messrs. Diffenbaugh and 

 Burke on the river banks near Philadelphia; Hb. n. 50. 



INDEX. 



The names of the species are in Roman type, those of the synonyms in Italics. 



J. abortivus, Chapm. 45G 



acuminatus, Michx. 462 



acuminatus, Auct. Am. 474 



acuti/iorns, var. Benth. 483 



acut'us, Lin. 438, 489 



atfinis, R. Br. 458 



alpinus, Vill. 458 



J. arcticus, Willd. 445,491 



arcticus, Hook. 445 



arcticus, var. Gray 446, 447 



aristatus, Pers. 455 



aristulatus, Michx. 455 



articulatus, Lin 458, 497 



asper, Eng. 478 



