Arisaema 



Araceae 



279 



o 5o 



Map 576 



Arisaema trlphyllum (L.) Schott. 



6 56 



Map 577 



Sp'rodela polyrhiza (LJ Schle'd. 



56 



Map 578 



lemna cyclostasa (Ell.) Chevalier 



2. Arisaema pusillum (Peck) Nash. (Arisaema deflexum Nieuwland 

 & Just, Amer. Midland Nat. 12: 217-220. 1931.) Map 575. A comparison 

 of specimens of Arisaema deflexum with a series of specimens of Arisaema 

 pusillum from Maine, Connecticut, Pennsylvania, and New York shows no 

 essential difference. In fact, Arisaema pvisillum itself seems to be only an 

 extreme form of Arisaema trlphyllum and it is reduced to synonomy in 

 Gray, Manual but is maintained as a species in Britton and Brown, Il- 

 lustrated Flora, ed. 2. Wiegand and Eames in their flora of the Cayuga 

 basin say: "It has not been possible to separate A. pusillum (Peck) Nash 

 in this region from the species (A. trlphyllum) by any constant char- 

 acters." My opinion is that this plant as found in Indiana is only a well 

 marked form or variety of the next species. It has been found as yet 

 only in St. Joseph County where it grew in bogs. 



Maine to N. Y. and Pa., along the coast to n. Ga. and reported in s. 

 Mich. 



3. Arisaema triphyllum (L.) Schott. (Arisaema trlphyllum (L.) Torr.) 

 Jack-in-THE-Pulpit. Map 576. Infrequent to frequent throughout the 

 state in moist, rich woodland. It is a shade-loving species, found from 

 the alluvial plains to the crests of the highest ridges and seems to have 

 no correlation with Arisaema Dracontlum in its distribution. A study of 

 my 69 specimens from Indiana shows that they have green and purplish 

 spathes but very few have the hood purplish above, none flower as late 

 as the middle of June, and none have been found in bogs. This species 

 is extremely variable in the color of its spathe, in the shape of the blade 

 of its hood, and in the shape of its leaflets. I have a specimen from 

 De Kalb County with 4 leaflets and one each from Lake and Steuben 

 Counties with the lateral leaflets parted. 



N. S. to Minn., southw. to Fla., La., and Kans. 



24. LEMNACEAE Dumort. Duckweed Family 



[Thompson, Charles Henry. A revision of the American Lemnaceae 

 north of Mexico. Ann. Rept. Missouri Bot. Gard. 9 : 1-43. 3 pi. 1898. Hicks, 



