Two imperfectly known species of Crataegus 



Francis Ramaley and G. S. Dodds 



So much misunderstanding exists in regard to certain Crataegi 

 of Colorado that further notes intended to clear up the difficulties 

 may not be amiss. Dr. Rydberg, in his excellent Flora* did not 

 extricate the species from the perplexity of much description. Two 

 of the best-marked species, C. Occident alls and C. color adensis , al- 

 though recognized by him as distinct, cannot be separated by the 

 use of his key. 



These two species were studied by Professor Cockerell f and 

 clearly separated. Unfortunately the names given by Professor 

 Cockerell are, by further study, found to be either incorrect or else 

 not the earliest. The present writers, after considerable field study, 

 are in a position to add certain characters not mentioned by him 

 and thus help to straighten out difficulties. Also, through the 

 courtesy of Dr. N. L. Britton, who has kindly reexamined his 

 type of Crataegus occidentalis, some characters may now be stated 



* 



in regard to the species which were not printed in the original 



description (length of petiole, pubescence of twigs, etc.). 



The synonymy of the two species under consideration is as 

 foil 



ows : 



Crataegus occidentalis Britton, Bull. N. Y. Bot. Garden i : 

 448. Mr 1898. 



C. Colorado Ashe, N. C. Agric. Exp. Sta. Bull. 175 : 1 10-1 13. 



Au 1 



900. 



C. macracantha occidentalis Eggleston, Rhodora 10 : 82. 1908. 

 In part. 



Crataegus coloradensis A. Nelson, Proc. Biol. Soc. Wash. 



17 • 175. D 1904. 



C. occidentalis Cockerell, Univ. of Colo. Studies 5 : 42. 1907. 



Not C. occidentalis Britt. 



* Rydberg, P. A. Flora of Colorado, Colo. Agric. Coll. Exp. Sta. Bull. 100 



! 92. 1906. 



t Cockerell, T. D. A. Univ. of Colo. Studies 5: 41-45- l°°7 



581 



