PLANTS OF ILLINOIS. 



39 



I apyracea, Ait. N. 



Lake shore about Chicago, (rare), Babcock; and j 

 Evanston, Vasey. 



nigra, L. C. & S. 



River hanks. Kankakee and Henderson coun- 

 ties and southward. Common. 



pumila, L. N. 



Wet places. Near Chicago, Munroe ; McHenry 

 county, Vasey. 



ALNUS 



serrulata, Ait. 



Bureau, McLean. Macon and Madison counties, 

 Miss Holmes ; White, Schneck ; Union, French. 



SALICACE.E. 



SALIX (By M. S. Bebb.) 



Candida, Willd. N. 



In cold bogs, Peoria county, Brendel : McHenry, 

 Vasey ; Cook, Babcock ; Winnebago ! Rare. 



tiistis, Ait. 



Sterile knolls and warm sandy prairies. Widely 

 distributed but Infrequent. 



humilis, Marshall. 



Prairies and barrens. Everywhere our most 

 common Willow. 



Mr. Walsh has described (Proc. Ent. Soc'y 

 Phila.) the "astonishing number of ten distinct 

 galls" produced by this species : the number 

 borne by other common Willows varying from 

 one to (usually) three or four. 



discolor, Muhl. 



Banks of streams, throughout. Common. 



Probably including several species confused 

 by cross fertilization. 



sericea, Marshall. 



Peoria county, Brendel. Rare. 



This species was published in 1785. S. peti- 

 OLARis was founded upon a cultivated plant, 

 supposed to be of British origin, and published 

 by Sir J. E. Smith (Linn. Trans. VoL 6) in 1802, 

 though the paper was received in 1801 : there- 

 fore, should the two be united as has been done 

 by Andersson, S. sericea should take precedence j 

 as the type of the aggregated species. 



petiolaris, Smith. 



Wabash county, Schneck : reported by others } 

 only at the north, where it is frequent. 



var. gracilis, Anders. 



Both forms, sericocarpa and leiocarpa, at 

 Fountaindale, Winnebago county. 



From S. sericea, Marsh, through this species 

 and S. ANG i stata, Pursh to S. cordata, Muhl. 

 an unbroken series of transitional forms occur — 



the result of cross fertilization — making the lim- 

 itation of species very difficult, if not purely 

 arbitrary- The hybrid skricea x cordata pre- 

 sents, very nearly, the technical characters of 

 S. i'etiolaris, Smith. 



adenophylla, Hook. N-E. 



Lake shore near Chicago, Babcock, Vasey. 



Retains under cultivation its remarkably dis- 

 tinct character : the tomeutose, glandular-serrate 

 leaves, very unlike those of any other Willow 

 occurring in the States east of the Mississippi. 



cordata, Muhl. 



Low, wet prairies and along streams. 



Common. 



(?) var. glaueophylla, Bebb. 



On the lake shore, associated with S. adeno- 

 phylla — Babcock ; Fountaindale, (only three 

 plants.) 



In the Willow garden at Fountaindale, where 

 several forms of this fine Willow sent by Mr. 

 Babcock are under cultivation, it has every ap- 

 pearance of being specifically distinct from S. 



CORDATA. 



rostrata, Richardson. N. 



Henderson county, Patterson ; otherwise only 

 reported from the northern counties, where it is 

 not uncommon. 



lucida, Muhl. 



Along streams, usually growing at the water's 

 edge. Common at the north. 



nigra, Marsh. 



Common along water courses, especially south- 

 ward. 



amygdaloides, Anders. 



(S. nigra, var., Anders, in DC.) 

 Peoria county, Brendel ,• Henderson, Patterson ; 

 Cook, Babcock ; Winnebago ! 



There is a similarity between the characters 

 Avhich distinguish this from the typical form of 

 S. nigra and those which separate S. petiolaius 

 from S. sericea. If S. petiolaris is admitted 

 as a valid species, S. amygdaloides claims equal 

 distinction. 



longifolia, Muhl. 



Wet places, throughout. Common. 



var. argyrophylla, Anders. 



Winnebago county ! 



myrtilloides, L. N. 



Cold peat bogs. Peoria county, Brendel : Mc- 

 Henry, Vasey. Rare. 



Widely distributed in sub-arctic regions, ex- 

 tending southward along the Pacific coast to 

 Oregon, and on the Atlantic side to New Jersey. 

 Its occurrence so far south in the Mississippi 

 valley as found by Dr. Brendel, taken in connec- 

 tion with the equally unexpected finding of S. 

 Candida, indicates an exceptionally cold spot for 

 the latitude. 



