1893.) Achenial Hairs of Composite. 381 
duplex and these specimens imperfect. 
merophyllus L. has some duplex only at the base and in 
‘other case three tips were distinguished. The lateral canals 
ae distinct, but their walls are sometimes broken, affording 
malsverse communications. In Aster laevis L. are found the 
W any Specific value. In many cases in Aster Nove-Anghe 
Variations are so great as not to offer any specific 
characters, 
“ga nudata DC. presents a: slight irregularity of ap- 
ie he canals seem to extend through the center of 
oe may, however, be due to the position and 
ine of the hair, which, combined, give to the division 
Proba le prearance ofacanal. This supposition seems more 
tevelo Ahad in the cases where only one half of the hair is 
Rudiess the canals are in the usual lateral position. ae 
tividee 3 . Pinnata Vent. introduces us to the group He ore 
ing. a aga a marked contrast to any of the pee 
™ one ca airs are much thicker and less acutely pea 
“other ee the canals seem to ramify irregularly. ed 
itd form h appears to be distinctly jointed, while : 
"etse “S the usual structure, lateral canals and trans 
10ns, 
lairs prondos L., also of the group ehaeriigesd 
aritj = 1, first to be simple but close study s pe 
Plex t ~ Of structure which would make them of : 
thas nae » at least in the more mature stages. The a 
“ght indica the younger growths are so distinctly sc le 
ate that the two parts do not always develop 
The asters all have long, distinct, duplex hairs. Aster 
the tips are deeply cleft and of unequal length, but here ~ 
