ORDER OF SUBJECTS 21 



of tlu> less practical and essential elements of ])liannacentical botany. 

 Still, it aids the student in the ai)i)licati()n of i)hytography and espe- 

 cially in understandinfj; distribution, and it serves to crystallize and 

 systematize his knowledge of groups of medicinal agents. A good 

 working knowledge of phytography may be regarded as the leading 

 essential. If the drug is to be sought by the pharmacist in nature, he 

 can recognize it only through phytography, whether that knowledge be 

 acquired through folk-lore or book-lore. If, on the other hand, he seeks 

 the crude drug in commerce, he merely restricts his phytography to the 

 plant-part under inspection, and so far from being by this consideration 

 relieved from phytographical labor, its requirements are the more exact- 

 ing and its methods the more refined, as the recognition and estimation 

 of a fragmentary representative becomes more difficult than that of the 

 complete individual. As "Phytography" in its ordinary employment 

 is about equivalent to "the study of the manifest organs of plants," 

 or of their gross units of structure, morphology becomes the key to the 

 situation. 



When drugs come to hand in a comminuted condition, the compound 

 microscope is the only resource, and the department of plant-histology 

 becomes the foundation of work. As will be shown farther on, the 

 greater portion of this subject can be passed over, but that portion 

 which receives attention, permitting the recognition of detached tissue- 

 elements and the determination by their examination of their source, 

 requires observations quite as careful and knowledge quite as accurate 

 as are called for in any other portion of the field. In the New York 

 College of Pharmacy, for the students of which this work is specially 

 prepared, the use of the compound microscope, and the subject of 

 histology, are separately taught, and the treatment of this important 

 subject is left to the appropriate department. 



Finally, we note that only an insignificant portion of the materia 

 medica includes the bodies of flowerless plants, so that the great division 

 of Cryptogamic botany, as regards its detailed treatment, is not essential 

 to Pharmacognosy. 



Order of Subjects. — In attempting a comparative view of the series 

 of plants, it is unquestionably well to begin with the lowest form and 

 follow the line, or rather lines, of ui)ward (kn-elo])ment; but in gaining 

 our first knowledge of the structure of the })lant organism, sound and 

 accepted rules of pedagogy require that we begin with the more obvious 

 characters of the higher plants, and pursue the analytic method, so far 

 as the special conditions of the case will ])erniit. 



