150 IOWA ACADEMY OF SCIENCES. 



has a peculiar gray color, quite distinct from the glaucous 

 under surface of 8. petiolaris. Neither the discoloration of the 

 foliage in drying nor the length of the petiole can be said to 

 be a good differential character as the discoloration is about 

 the same in both species and the petioles of >S'. sericea are 

 scarcely shorter than those of S. petiolaris. The aments are 

 small but dense. The capsules are ovate-oblong, one to one 

 and one-half lines in length, subsessile. Time of flowering. 

 May. 



Fayette, Fayette Go. 18, Fink, Herb.; Solon, Johnson Oo. 37, Shimek, S. U. I.; 

 Keokuk, Lee Co. 46, Rolfs. 



X. SALIX PETIOLARIS SMITH. 



Salix petiolaris Smith. Trans. Linn. Soc. 6: 122 1802. 



The petioled willow is not very common in Iowa and yet is 

 sparingly distributed over the greater part of the state. It is 

 a shrub of from five to ten feet in height and is found in low 

 grounds like the preceding. The twigs are reddish or yel- 

 lowish, deepening to purplish. Typical leaves of the two 

 species are not difficult to distinguish at sight, yet a descrip- 

 tion of one will apply almost equally well to the other. The 

 leaves of S. petiolaris are narrowly lanceolate, silky, until 

 unfolded, glaucous below, acute at both ends, midribs and 

 petioles usually yellowish. The petioles are from two to five 

 lines long, but not distinctly longer than those of S. sericea. 

 The leaves are generally discolored in drying. 



The aments are one inch long or less, the staminate are 

 slender and of a golden brown color. Mature capsules are 

 slender, three to four lines long; pedicels one-half line in 

 length. The short scales are generally green at the base and 

 red or dark at the tip. Time of flowering, May. 



Obarles Olty, Floyd Co. 14. Arthur {2 spec, one in the Engelm Herb.) ; Fort Dodge, 

 Webster Oo. 20. Shimek, S. U. I.; Ames. Story Oo. 28. Pammel (No. 1207) Ball and Sample 

 (No. 1208) ; Johnson Co, 36. Shimek, S .U. I.; Eldrldge, Scott Co. 38. Barnes and Miller (3 

 spec., Nos. S, 15, 17). 



XI. SALIX CANDIDA FLUEGGE. 



Salix Candida Fluegge (in litt.). Sp. Plant. 4: 708. 1806. [ed. 

 Willd.] 



This pretty little willow frequents cold bogs and is rare in 

 Iowa. It can be readily recognized by its narrowly oblong- 

 lanceolat® leaves, densely white tomentose below and loosely 

 so above. The aments are not large, but the capsules are one- 

 fourth inch in length, ovoid conic and densely white tomentose. 



