220 LEAFLETS. 
I have been unable to ascertain that any authority upon genera 
or generic nomenclature, whether of the nineteenth century or 
the twentieth, has hitherto discovered this. Every one of them 
seems to have been misled by the name PsEpERA, Neck. This 
is really Pseudohedera with certain syllables eliminated, partly 
for the sake of brevity, but more for the purpose of keeping it 
from falling under the ban of that excellent article of Linnaeus’ 
Code which prohibits the use of generic names formed by pre- 
fixing Pseudo to another name. The name itself, therefore, must 
have beguiled the superficial into guessing that PsEDERA is some 
segregate of Hedera: and this guess has found expression in 
certain well known bibliographies. But the authors can hardly 
be supposed to have looked beyond the mere name itself. The 
character ascribed to PsSEDERA by Necker is in accord with that 
of Planchon’s Parthenocissus in all essentials. But what places 
my identification of PsEDERA with Parthenocissus beyond all 
cavil is the circumstance of Necker’s having stated one of Lin- 
naeus’ Hedera species to be its type; for of that genus the species, 
with Linnaeus, are but two. 
Only the American species of PSEDERA at present concern me. 
P. QUINQUEFOLIA. Hedera quinquefolia, Cornut (1635), Linn. 
(1753), Mill. (1768). Vitis quinquefolia, Tourn. (1700), Lam. 
(1793), Moench (1794). 
P. HIRSUTA. Ampelopsis hirsuta, Roem. and Schultes (1819). 
P. VITACEA. Parthenocissus vitacea, Hitchc. (1894). 
P. TEXANA. Parthenocissus Texĝna, Rehder (1905). 
P. LACINIATA. Ampelopsis quinquefolia var. laciniata, Gray in 
Planchon (1887.) 
