1912] Fernald, — Variety of Spiraea tomentosa 189 
paratively short (not lanate) tomentum is promptly deciduous so 
that the lustrous and glabrate surfaces of the follicles are apparent. 
Attempts to find other characters have failed for in foliage the two 
plants closely simulate one another, the leaves of both varying in 
outline from lanceolate to ovate-oblong, with the tomentum of the 
lower surface from white to rufous; and occasional individuals from 
the coastal region have an open inflorescence and distinct pedicels but 
lanate follicles. The writer therefore does not feel justified at present 
in treating the plants as distinct species; but as geographic varieties 
they are well marked and deserving of recognition. 
Judging from the Linnean description of Spiraea tomentosa which 
came from Philadelphia (Kalm) and was compared with S. salicifolia 
in the following terms: Differt a praecedenti....racemo terminali 
composito densiori longiori," + there is no question that he meant the 
densely flowered shrub of the Coastal Plain and adjacent regions; but 
the Plukenet plate of “Ulmaria pentacarpos, integris serratis foliis 
parvis subtus incanis, virginiana," ? cited by Linnaeus as belonging to 
Spiraea tomentosa has the open inflorescence and slender pedicels of 
the more inland shrub. 
In his New Flora Rafinesque divided Spiraea tomentosa into five 
species with the characteristic comment: “All the above sp. agree 
in nothing but the tomentous leaves beneath, to deem them all varie- 
ties would be preposterous, as no character including them all could 
befound." Besides true S. tomentosa Rafinesque defined S. ferruginea 
with “flowers subsessile”; S. glomerata with “flowers subsessile 
glomerate"; S. parvifolia with “panicle spicate glomerate, flowers 
sessile”; and S. rosea with “panicle lax, peduncles [pedicels] as long 
as calix— West Kentucky to Alabama, disc. by Mrs. Holley, a 
beautiful shrub with fine rosate flowers, it deserves to be deemed a 
peculiar sp. by narrow leaves not white beneath, and lax rose flowers." * 
From the description and the range of Rafinesque's S. rosea there can 
be no question that he had the more loosely flowered extreme of S. 
tomentosa, with glabrate follicles; but the shrub cannot be separated 
from typical S. tomentosa “by the narrow leaves not white beneath" 
since the foliage varies in both these characters as much as that of 
true S. tomentosa; and, as already stated, the characters of the in- 
1 L. Sp. PL, 489 (1753). 
? Pluk. Alm., 397, t. 321, f. 5. 
3 Raf. New Fl., iii. 62, 63 (1836). 
