tfchuette — Hawthorns of Northeastern Wisconsin. 93 



Since the nomenclature of Crataegus seems to be somewhat 

 unsettled, I have employed the familiar names while embodying 

 my own views in the following descriptions. A series of speci- 

 mens, including the types of the new forms, has been presented 

 to the Biological Society of Washington, and by the latter 

 turned over to the United States National Museum. 



Artificial Key to the Hawthorns of Northeastern Wisconsin. 



I. Fertile shoots of the current season pubescent. 



1. Leaves cordate, truncate or rounded at base, tomentose beneath; 

 petioles not margined, tomentose 1. C. subrillosa Schrader. 



2. Leaves acute or acuminate at base; petioles margined. 



a. Sepals (calyx lobes) toothed (glandular in No. 3). 



* Anthers red; petioles and outer surface of sepals pubes- 

 cent; flowering two weeks later than No. 1 



2. C. tomentosa L. 



** Anthers white; sepals glabrous outside (sometimes 



hairy at base) - - 3. C. macracantha Lodd. 



b. Sepals entire, glandless, their outer surface glabrous in the 

 upper half - - - - 4. C. punctata Jacq. 



II. Fertile shoots of the current season glabrous. 



1. Corymb and calyx pubescent; sepals deeply (almost fimbriately) 

 toothed; petioles not more than one-sixth as long as the blade, 

 margined, groove hairy and impressed. 



a. Anthers red; stamens 12-20; calyx cup hairy; leaves hairy 

 beneath, especially on the nerves 5. C. pyrifolia Ait. 



b. Anthers white in bud, gradually turning brown; stamens 

 8-12 (rarely more), calyx cup and leaves beneath usually 

 glabrous - - 6. C. pyrifolia sylvestris subsp. nov. 



2. Corymb and calyx cup glabrous* ; sepals slightly dentate or en- 

 tire; petioles at least one-third as long as the blade, glabrous 

 beset with few glands. 



a. Anthers white; sepals toothed and conspicuously gland- 

 ular; petioles margined, blade acute at base, its teeth 

 more or less obtuse if the small terminal gland is re- 

 moved - - - - 1.C caliciglabra sp. nov. 



b. Anthers red; sepals with few gland-tipped teeth or entire 

 and glandless; petioles marginless by tightly inrolled 

 edges, filiform, visually more than one-half as long as the 

 blade ... 8. G. coccinea L. 

 (For subspecies see below, description No. 8). 



* In some forms of C. coccinea slightly scattered with soft hairs, but 



glabrate. 



