144 AMERICAN MIDLAND NATURALIST 



wise when young, 2-6 cm. long, 1.5-4.5 C"^- broad (comparatively 

 broader than in A. ohlongijoUa), older of very firm texture, bright- 

 and deep-green, strongly veined, irregularly serrate-dentate, 

 especially on the upper two-thirds of their margins, with small 

 callous-tipped teeth, but other leaves have only a few, very small 

 teeth, and still others have even entire margins. Petals about 

 8 mm. long, obovate. Fruiting pedicels 3-10 mm. long. Pome 

 juicy, sweet, black or black-purple, 10 mm^. in diameter, ripe 

 during the latter part of June-July, while the species is flowering 

 from the last part of April until the first part of June. It reaches 

 its largest size in moist woods, and is comparatively small in rocky 

 uplands.* Besides being planted for its ornamental eflfect in lawns, 

 this shrub is highly valued for culinary purposes on account of 

 its large, delicious pomes. To the laity, however, the size does 

 not entitle them to such a dignified rank, but simply reduces them 

 to "berries," as a pome is expected to have at least the size of a 

 crabapple. 



Usually distributed as A. alnijolia Nutt., but this shrub has 

 leaves glaucous and coarsely crenately serrate-dentate above the 

 middle, entire below the middle, and coming nearer to the orbicular 

 outline than ours; the pomes are purple with bloom, 6-8 mm. in 

 diameter. It grows on banks of streams. Our species is nearest 

 related to A. oblongijolia (T. & G.) Roem., but this shrub has 

 leaves oblong, 4-6 cm. long, 1.5-2.8 cm. broad (thus narrower 

 than ours), finely and evenly serrate, light-green, and its pome is 

 smaller, 6 mm. in diameter, and crimson or purplish. 



The type was collected by the writer at Pleasant Lake, Benson 

 County, on May 21, 1912 and July 28, 191 1. 



Rhus angustiarum sp. no v. 



Caudex subterraneus ramos caudicibus similes sursum versus 

 emittens, anno i: mo pedales, 2 : do 3-pedales, 3:0 5-pedales, 

 4: to 7-pedales. Pars tota lignea nuda, gemmis lucidis succulentis 

 in locos foliorum priorum substitutis, fusca, lenticellata. Apices 

 herbacei tempcstivi er pctioli tegmento glauce scente purpureo- 

 maculoso primitus vestiti, tarde obscure spadices, glutinosi. Folia 

 15-30 cm. longa, valde conferta. Fohola 13-17, interdum 19, 

 mensura et forma admodum variabilia, 3-9 cm. longa, oblongo- 

 lanceolata, apice acuminato vel acuto, basi rotundata, foliola 

 foliorum superiorum ramorum frugiferorum panee sessilia, foliorum 



