1)6 JOURNAL OF THE ARNOLD ARBORETUM [vol. hi 



styli ramuli paullo vel satis pruinosi sunt). Confer 106. S. bellam, 104. S. 

 pellitam, 102. S. planifoliam et 105. S. subcoeruleam. 1 



= = Ramuli nunquam pruinosi. 



Bracteae concolores, flavescentes, partim ad apicem rubescentes; glandula 

 linearis, quam bractea paullo brevior; amenta anguste cylindrica, sessilia vel 



subsessilia; species rara calif ornica 109. S. Breweri. 



Bracteae bicolores, ad apicem vel omnino fuscescentes vel brunnescentes (in 

 S. commutata satis flavo-brunneae) ; glandula vix distincte linearis, quam 

 bractea saepissime plus quam duplo brevior. 

 Amenta sessilia vel subsessilia, praecocia vel subcoetanea, basi subnuda vel 

 tantum foliolis parvis squamiformibus instructa.' 2 

 Pubescentia bractearum florum sericea pilis satis strictis superioribus quam 

 bractea vix brevioribus. 

 Ramuli etiam novelli tantum sparse pilosi vel ab initio glabri; filamenta 

 interdum paullo coalita. 3 

 Bracteae satis late obovatae; folia superne estomatifera; stipulae saepis- 

 sime nullae. (Confer etiam 96. S. Scoulerianae formas glabras). 



79. S. Piperi. 



Bracteae satis oblongae, obtusae vel subobtusae; folia superne stomati- 



fera; stipulae saepissime distinctae 66. S. monticola. 



Ramuli praesertim hornotini tomentosi vel villoso-tomentosi; filamenta 

 normaliter libera. 



Amenta ad apicem ramulorum brevium lateralium 1-2 pseudoter- 

 minalia 75. S. calcicola. 



Amenta in ramulis elongatis plura lateralia. 



Antherae initio (an semper?) violaceae; amenta vix ultra 2 : 1.2 cm. 

 magna; ramuli floriferi vix plus quam 2(-2.5) mm. crassi. 



'93. S. humilis. 



Antherae etiam initio semper flavae vel aureae; amenta saepissime 

 longiora vel crassiora; ramuli floriferi plerique (2.5-) 3-4.5 mm. 

 crassi. Confer 78. S. Hookerianam, 99. S. Rowleei et 96. S. Scouleri- 

 anae formas. 

 Pubescentia bractearum florum crispo-sericea pilis partim vel omnibus plus- 

 minusve crispis vel etiam superioribus quam bractea vix longioribus. 4 

 Ramuli floriferi lutescentes vel flavescentes (saepe partim rubescentes); 

 amenta 2-3.5(-4) cm. : 8-10 mm. magna, subsessilia, basi bracteolata 

 vel foliis minimis 2-3 integris vel minute denticulatis suffulta; bracteae 

 oblongae, acutiusculae, satis longe laxe sericeae .... 60. aS. lutea. 

 Ramuli floriferi fusci, brunnescentes vel castanei, interdum pubescentes 

 vel tomentosi. 

 Bracteae obovatae, apice plusminusve rotundatae obtusaeve, extus 

 saltern dense albo-sericeae (pilis saepe satis brevibus); amenta 2-4: 

 0.8-1 cm. magna (in var. Iligclovii ad 6:1.2 cm.), praecocia, sessilia 

 basi bracteolis paucis minutis dense sericeis deciduis obsita. 



55. S. lasiolepis. 



Bracteae vix obovatae, oblongiores, acutiores vel glabriores vel amenta 

 basi foliolis paucis suffulta. 



1 See the key given in this Jour. I. 69. 



It is almost impossible to distinguish male specimens of these species without the aid 



of the leaves. 



2 It sometimes happens that species of which the aments mostly are precocious may 

 develop a distinct peduncle with small leaves. On the other hand, species like for 

 instance S. glaucophylloides or S. pyrifolla, not unfrequently bear rather precocious 

 male aments with only a few small bracts at their base. 



3 See also the species mentioned above S. bella, S. pellita, S. planifolia and S. sub- 

 coerulea of which the flowering branchlets sometimes are hardly pruinose, but the 



filaments are always free. 



4 This refers to the species of section Cordatae of which the bracts sometimes are 

 suh^labrous, but mostly their hairs are somewhat curled, a feature that gives to the 

 whole appearance of the pubescence of the aments a rather peculiar character. 



