CONTRIBUTIONS FROM THE GRAY HERBARIUM OF HARVARD 

 UNIVERSITY. — NEW SERIES, No. XXXVI. 



Presented by B. L. Robinson, March 10, 1909. Received March 12, 1909. 



I. SYNOPSIS OF THE MEXICAN AND CENTRAL AMERICAN 



SPECIES OF CASTILLEJA. 



By Alice Eastwood. 



The genus Castilleja was published by Linnaeus fil. in 1771 (Suppl. 

 293). It was named by Mutisin honor of Domingo Castillejo of the bo- 

 tanical garden of Cadiz and rested upon the two species collected by 

 Mutis in New Granada, C. integrifolia and C. fissifolia. At that time 

 C. pallida and C. coccinea had been described by Linnaeus but under 

 Bartsia, so that altogether four species were known. In 1818 Nuttall 

 established the genus Euchroma (Gen. ii. 55) founded upon Bartsia 

 coccinea and B. sessilijlora Pursh. The first satisfactory arrangement, 

 however, came in 1846, when Bentham revised the genus Castilleja 

 (DC. Prodr. x. 528-534), establishing four sections. At that time 

 thirty-four species were known, fifteen of which belonged to Mexico 

 and Central America. The subdivisions established by Bentham seem 

 to mark off natural groups, which, however, show connecting charac- 

 teristics that often render the true position of certain species doubtful. 

 Epichroma is probably the most individual subdivision and has, per- 

 haps, the best claim to generic rank ; but some species placed in the 

 present synopsis under Euchroma have floral characteristics that closely 

 approach those of Epichroma, while other species under the same section 

 are difficult to separate from Hemichroma. On account of this inter- 

 relationship any key must be more or less artificial. Perhaps when 

 the knowledge gained from books and herbarium specimens is supple- 

 mented by that of the living plants in their natural environment, an 

 entirely different system of classification may be arranged. Dried 

 specimens often conceal the form of the flower, and when mounted 

 frequently render dissection difficult, so that it is not always possible 

 to obtain accurate knowledge of all of the parts ; especially is this true 

 of the lower lip of the corolla, which gives much of the characteristic 



