CRATAEGUS IN MISSOURI. 39 



flowering and fruiting of these plants in the Arboretum 

 that first showed me the variety and importance of the 

 Missouri Crataegus flora and led me to undertake its 

 investigation. 



It is a great satisfaction to me that the results of this 

 investigation appear among the publications of the Missouri 

 Botanical Garden; for Professor Trelease has often been my 

 companion in journeys made for the purpose of studying 

 Crataegus in the field ; and the resources of the Garden for 

 manv vears have been freelv devoted to aiding these studies. 



SYNOPSIS or GROUPS. 



A. Nutlets without ventral cavities. (Groups Crits-galli to Micro- 



CARPAE.) 



a. Veins of the leaves extending to the points of the lobes only. 



(Groups Crus-galli to Uniflouae.) 



b. Veins of the leaves extending to the points of the lobes and to the 



sinuses. (Group Microcaupae.) 



B. Nutlets with longitudinal cavities on their ventral faces. (Group 



TOMENTOSAE.) 



CRUS-GALLI, 



Leaves subcoriaceous to coriaceous or less commonly thin, obovate to oval, 

 ovate or rhombic, cuneate at the base, usually serrate only above the 

 middle, without lobes except on vigorous shoots, their veins usually thin 

 and often within the parenchyma; petioles short, usually eglandular; 

 fruit subglobose to short-oblong, oval or ovate, 7-25 mm. in diameter, 

 with thin usually greenish flesh; nutlets 1-3, rarely 4 or 5. 



Leaves subcoriaceous to coriaceous. 



Corymbs, leaves and branchlets glabrous or slightly hairy while 



young. 



Stamens 8-10 (occasionally 15 in No. 2, 5-10 in No. G, and 



5-8 in No. 13). 



Anthers rose color or pink. 



Leaves oblong-obovate, rounded or occasionally 



r 



acute at the apex. 



Flowers in 15-20-fiowered corymbs; anthers 

 pink; fruit short-oblong to ovate, dull red. 



1. C, stro7}gyIophijlla. 



Flowers in 10-18-flowered corymbs; anthers 

 10-15; styles 3-5; fruit short-oblong to 

 subglobose, dull red blotched with green. 



2. C. discolor. 



