Bor.-Am.  i,  275;  Companion  Bot.  Mag.  i,  48. — Don,  Miller's  Diet,  iii,  396,  f.  69. — Beck,  Bot.  152. — Eaton,  Manual  6  ed.  164. — Spach,
Hist,  Veg.  viii,  79. — Dietrich,  Syn.  i,  550. — Torrey  &  Gray,  Fl.  N.  America,  i,  597. — Loudon,  Arboretum,  ii,  1007,  f.  756,  757. —
Eaton  &  Wright,  Bot.  260.— Bigelow,  Fl.  Boston.  3  ed.  63.— Emerson,  Trees  Massachusetts,  416 ;  2  ed.  ii,  473  &  t.— Darby;  Bot.  S.
States,  328.— Darlington,  Fl.  Cestrica,  3  ed.  98.— Agardh,  Theor.  &  Syst.  PI.  t.  13,  f.  7.— Schnizlein,  Icon.  1. 167,  f.  18-25,  27-29.—
Gray  in  Am.  Jour.  Sci.  2  ser.  xxiv,  438;  3  ser.  v,  144;  Manual  N.  States,  5  ed.  173.— Chapman,  Fl.  S.  States,  157. — Curtis  in  Eep.
Geological  Surv.  N.  Carolina,  iii,  105. — Lesquereux  in  Owen's  2d  Eep.  Arkansas,  362. — ^Wood,  CI.  Book,  375 ;  Bot.  &  Fl.  120. —
Engelmann  in  Trans.  Am.  Phil.  Soc.  new  ser.  xii,  193. — Porcher,  Eesources  S.  Forests,  58. — Koch,  Dendrologie,  ii,  458. — Baiilon  in
Adansonia,  x,  123;  Hist.  PI.  iii,  389,  f.  462-464.— Young,  Bot.  Texas,  291.— Maout  &  Decaisne,  Bot.  English  ed.  408  &  f.
H.  dioica,  Walter,  Fl.  Caroliniana,  255.— Gmeliu,  Syst.  Veg.  i,  281.
H.  androgyna,  Walter,  Fl.  Caroliniana,  255.— Gmeliu,  Syst.  Veg.  i,  282.
H.  corylifolia,  Moencb,  Meth.  273.
H.  macrophylla,  Pursb.  Fl.  Am.  Sept.  i,  116.— Poiret,  Suppl.  v,  698.— Elliott,  Sk.  i,  220.— EajmSr  &  Schultes,  Syst.  iii,  483.—
Eaflnesque,  Med.  Bot.  i,  230.— Eaton,  Manual,  6  ed.  164.— Don,  Miller's  Diet,  iii,  396.— Eatou  &  Wright,  Bot.  261.
Trilopus  Virginiana,  nigra,  rotundifolia,  and  dentata,  Eafinesque,  New  Sylva,  15-17.
