125 
do not maintain a spiral arrangement similar to the aborted flowers, 
but an examination of the plant would readily show that displacement 
IS unavoidable. Of the flowers, one of those at the side blossoms 
first, then the one on the opposite side, and lastly the one in the 
Kq jo 
S 
^ 
ri6 8 Fi^.9 
O 
middle. The arrangement of the various flowers has not been suffi- 
ciently studied to seU/e the phyllotactic arrangement of those 
on the a«:is of the raceme. How necessary bees are to insure fertili- 
zation may be seen from the fact that those clusters which escape the 
attention of bees by being too much hidden by the surrounding 
foliage, never spring the keel, so that the flowers wither and die with- 
out the keel being loosened. (Gray, Struct. Bot. p. 218). Flowers 
thus unsprung seem to last longer.* 
In connection with this it may be interesting to note that in TY/ia 
Americana (Fig. 5) Cqtalpa speciosa (Fig. 6) and Ailanthus glandu- 
losus (Fig, 7) the terminal part of the leaf branches falls off, leaving 
^ clean scar {sc). The branches are continued by buds in the axils 
of lower leaves. In Hamamelis Virginica (Figs. 8, 9 and 10) the 
leaves fall off in autumn and leave a scar. In the following spring a 
plane has been formed just beneath the scar of the former year. At 
this plane the leaf-scar of the former year falls off leaving another scar 
for the spring time. This singular phenomenon might be called that 
of a '* deciduous leaf-scar." The accompaning drawings will make 
unnecessary all further description. 
Description of Figures. — Apios tuberosa. Fig. i. Entire raceme seen from 
^bove. Fig. 2. The same x 5; flowers fallen off, pedicel of middle flower remain- 
'"g: «, truncated axis of the raceme; b, bract subtending the middle flower; r, bract 
suDtending the raceme; d, circular depression left by the pedicel of the flowers. 
'S- 3. Truncated axis of raceme x 5, showing attachment of flower-pedicels. Fig. 
4- Deciduous end of the panicle, fig. 5. Tijia Americana: scar, s c, of leaf-branch. 
^g* 6. Catalpa speciosa: scar, J c, of leaf-branch. Fig. 7. Ailartthus glandulosus : 
^^^y s c, of leaf-branch. Figs. 8 and 9. Hamamelis Virginica; front and side 
views of leaf-scar before falling off. Fig. 10. Deciduous leaf scar. 
New Grasses. 
By George Vasey. 
Stipa Scribnert. — Culms 2-3 ft. high, stout, erect; lower leaves ^ 
half 
as long as the culm, smooth, flat below, becoming involute at 
* Note. The following from Prof. Trelease is of interest; "The sort of 
gj^nds you find in Apios are also found in other Leguminosse. e.g. , species of Dolichos 
^naseolus, and Canavalia. I have noticed them in all but the last named genus; 
probably they occur in many others. 
References: Trelease, in Comstock's Report on Cotton Insects, 1879, 325; 
^'«5n<raw Bee Joural, 1880, xvi. 271-2., Figs. 9-10. Delpino, in Atti della R. 
^"^versita, Genova, i83o, iv., part i. p. 27." 
