212 



delicate; forms with large leaves, dense foliage, and close-set 

 branches are much better than varieties with small leaves, 

 skimpy foliage, and scattered branches. In the second place, it 

 is essential that the material should be soft and flexible, and at 

 the same time that it should possess a considerable degree of 

 strength. Here again there is great variation between different 

 species. In general, coarse or stringy forms, or forms with stiff or 

 brittle stems or harsh texture, must be avoided. 



Of all the sphagnums, there is one species which combines, to a 

 greater degree than any other, absorbency, softness, and strength. 

 This is Sphagnum papillosum. This species, at least here in the 

 east, has been found to be much more satisfactory for use in 

 surgical dressings than any other variety. Three other species of 

 sphagnum have been used to a considerable extent in surgical 

 w^ork, namely S. palustre, S. magellanicum, and S. imbricatum; 

 but while in the humid climate of western Washington and British 

 Columbia these develop quite as luxuriantly as S. papillosum, 

 and while locally, here in the east, they may compare very 

 favorably, on the whole they tend to have too much stem in 

 proportion to foliage or too harsh a texture to make ideal surgical 

 material. In the field S. papillosum can usually be recognized 

 by its very robust habit and brownish color: it is never red or 

 purple. As a rule the other three species named are less robust; 

 S. magellanicum commonly is pink or purplish red in color, S. 

 palustre pale greenish white, and 5. imbricatum green. 



In this connection it should be emphasized not only that 

 different varieties of sphagnum exhibit a wdde range of 

 variation when it comes to their capacity for absorbing liquids, 

 as well as to other features which adapt them to surgical use, 



Plate 218, lower figure, i. Sphagnum recurvutn. 2. S. capillacentn lenellum. 

 3. 5. Girgensohnii. These three and similar forms are mostly worthless for surg- 

 ical work. 4. 5. plumulosutn flavicomans. This species is sometimes used for 

 surgical dressings. 5, 6, 7. 5. magellanicum. Material like No. 7, which is soft and 

 very f uU-foliaged, and No. 6, which is less bushy but very soft, make excellent surg- 

 ical material. These specimens grew in the water. No. 5 illustrates the usual habit 

 of this species — very stemmy, sparsely branched, and rather harsh. Such material 

 is useless. 8, 9. S. papillosum. These two specimens and Nos. 6-8 illustrate the 

 range of variation exhibited by the same species under different conditions of 

 environment. Moss like Nos. 7 and 9 furnishes the best surgical material. 



