122 American Midland Naturalist Monograph No. 7 



2. Leaves irregularly toothed, notched, or lobed, narrowed at the 

 base; calyx-lobes erect or spreading; fruit 3-5 cm in diameter; 

 woods, common. May. Iowa Crabapple. [Pyrus ioensis 

 (Wood) Bailey] M. ioensis (Wood) Britt. 



2. Leaves crenate-serrate, rounded or cordate at base; calyx-lobes 

 usually reflexed at anthesis; fioiit larger; cultivated, and not 

 infrequently wild; native of Eurasia. Apr. -May. Apple. 



[Pyrus malus L.; M. sylvestris of auth., not Mill.] 



„ M. pumila Mill. 



19. Crataegus L. — Hawthorn 

 1 Leaves widest near the middle or toward the apex, cuneate at the 

 base. 

 2. Blades usually widest above the middle, mostly obovate or 

 spatulate, the margins merely serrate or only obscurely lobed; 

 calyx-lobes entire. 

 3. Veins of leaves rimning to sinuses as well as lobes; cultivated, 

 but rarely spontaneous in 111.; Cook Co., V. H. Chase. 



English Hawthorn C. monogyna Jacq. 



3. Veins of leaves running only to lobes. 



4. Leaves fimi, glossy above, not deeply impressed-veined. 

 5. Pedicels and lea\es glabrous; pastures and open woods, 

 especially near streams, common. May-June. Cock- 

 spur Thorn. \C. attenuata Ashe; C. arduennae, 



barrcttiana, calophylla, fffulgrns, jarwellii Sarg.] 



C. crusgalli L. 



5. Pedicels and leaves pubescent; wooded hillsides and 



bluffs in s. 111. May-June. [C. pilifera Sarg.] 



- C. engebnanni Sarg. 



4. Leaves thinner, dull, impressed-veined above. 



6. Pedicels and leaves glabrous; open woods, usually along 



streams; in the northern half of the state, Fulton, 

 Peoria, Stark, and Will counties. May-June. [C. dis- 

 perma, grandis Ashe; C. peoriensis Sarg.; C. hannibal- 



ensis Palmer] C. cuneiformis (Marsh.) Egglest. 



6. Pedicels and leaves pubescent, at least when young. 



7. Terminal leaves obovate, deeply lobed; pastures and 

 open woods throughout 111. May-June. [C. praten- 

 sis Sarg.]. A form with yellow fruits, f. aurea (Ait.) 



Rehd., occius in 111 C. punctata Jacq. 



7. Terminal leaves elliptical, not lobed or only slightly 



lobed; swampy woods, rare; Jackson Co 



C. collina Chapm. 



2. Blades prevailingly widest near the middle; calyx-lobes usually 

 glandular-serrulate. 



8. Blades more or less pubescent beneath, at least in the axils of 

 the veins; pedicels pubescent. 



