18 KEY, BASED UPON FKUIT. 



/ J . Style or remnants of it ; fruit about 



- in. long, dryish, in racemes 107. CYRILLA RACEMIFLORA. 



i in. long, juicy, in cymes 157. SAMBUCUS GLAUCA. 



f z . Not crowned with either calyx-teeth or style, 

 y. Sessile, scaly-bracted beneath ; leaves evergreen. 



Dark blue, seeds 1-4 25. JUNIPERUS VIRGINIAN A. 



Blue-black, seeds 2-3 168. JUNIPERUS OCCIDENTALS. 



Reddish-brown, seeds 1-2. 167. JUNIPERUS CALIFORNIC A. 



</ 2 . Pedicellate, not scaly-bracted beneath, slightly 2-3-lobed, 2-3-seeded, 



Black; nutlets indehiscent 126. RHAMMUS PURSHIANA. 



Red; nutlets dehiscent 176. RHAMMUS INSULARIS. 



c 4 . Nut hard, single coat and furnished with an involucral cup or covering. 

 d. Ovoid oblong or ellipsoidal, surrounded at its base with an involucral 



cup (Quercus), acorn borne 

 e. On the new wood of the season (i. e. maturation annual) cup 



/. Less than enveloping the oval acorn 136. QUERCUS GARRY ANA. 



f^. About i enveloping the small 



Ovoid nut in. long : scales thin 68. Q. MUHLENBERGII. 



Long, narrow nut, often 2 in. long 160. Q. LOBATA. 



f 3 * About ^ enveloping the nut 

 </. Thick, scales very roughly tubercled, edge of cup rather inturned after 



shedding the nut ; nut usually long-ovoid 38. Q. ALBA. 



f/ 2 . Thinner, scales thinnish ; leaves 



Deciduous; peduncles shorter than petioles .... 67. QUERCUS PRINUS. 

 Subpersistent ; acorns sessile or nearly so. .137. QUERCUS AGKIFOLIA. 

 f 4 . Scarcely enveloping the oblong-ovoid nut about 1 in. in length. 



116. QUERCUS MICHAUXII. 



/ 5 . About | or more enveloping the nut ; peduncles longer than the 

 petioles ; nut 



f in. long, light brown 66. QUERCUS BICOLOR. 



| in. or less long, dark brown 117. QUERCUS VIRENS. 



f 6 . About | or more enveloping the nut ; peduncles 



(j. Longer than the petioles 66. Q. BICOLOR. 



y*. Shorter than the petioles ; scales 



Very loosely appressed, forming a moss-like fringed margin of cup. 



39. Q. MACROCARPA. 



More closely appressed and not forming a moss-like fringe. 



92. Q. OBTUSILOBA. 



e 2 . On wood of the preceding season (i. e. maturation biennial) ; cup 

 /. Very shallow, almost flat and with long-linear recurved scales. 



138. QUERCUS DENSIFLORA. 

 / 2 . Saucer-shaped, 



One-fourth enveloping the nut which is 



1 in. or less in length; saucer thin 15. Q. RUBRA. 



1 in. long ; saucer thin at rim 191. Q. TOMENTELLA. 



2 in. or less in length ; saucer usually thick 161 Q. CHRYSOLEPIS. 



One-half enveloping an ovoid nut 162. Q. CALIFORNICA. 



0r 2 . Flattened-globose ; leaves 



Sinuate-pinnatifid with wide sinuses 94. QUERCUS PALUSTRIS. 



Obovate-spatulate, entire 118. QUERCUS AQUATICA. 



y 3 . Top-shaped, | enveloping the acorn ; scales thin and coarse ; 



Inner'bark of tree reddish 69. Q. COCCINEA . 



Inner bark yellowish 93. Q. TINCTORIA. 



f 1 . Turbinate, enveloping the nut 192. Q. WISLIZENI. 



d 2 . Club-shaped, short, surrounded with stiff hairs, tipped with the persistent 

 recurved style and arranged in globular heads, which are 



Solitary 13. PLATANUS OCCIDENTALS. 



2-7 together in a uioniliform spike 135. PLATANUS RACEMOSA. 



d 3 . Achenium-like, small and borne in short catkins, 



Inclosed in a membranous inflated sac, catkin hop-like. 



41. OSTKYA VlRGINICA. 



Subtended by a large leafy bract 42. CARPINUS CAROLINIANA. 



c 5 . Nut-like, dry, not invested with an involucre, 



