LEAVITT: TRICHOMES OF ROOT. 
275 
gandi, A. Williamsii, Aspidium Jilix-mas, A. marginale, A. 
molle , A. trifoUatum , Asplenium angulare, A. bidbiferum , A. 
decussatum, A. Trichomanes, Blechnu.m brasiliense, B. occiden¬ 
tals, B. spiccins , Cyrtomium sp., Gymnogramme sulphurea , 
Lomaria gibba , Microlepia hirta, Bavallia jvjiensis, Doodia 
rupestris , Neplirodium Shepardii, Nephrolepis bulbifera , iV7 
davallioides , 2V! exaltata , Onoclea sensibilis, Pellaea hastata, 
P/iegopteris polypodioides, Platycerium Alcicorne , Polypo¬ 
dium aureum , plectolepis , P. vulgare , Pteris aurata, P. 
cretica , P. pedata , P. serrulata, P. tremula, Scolopendrium 
vulgare, Woodsia obtusa, Wood war dia angusti folia. 
Osraundaceae : Osmunda regalis. 
Marattiaceae : Angiopteris evecta , Afarattia alatct. 
In Ophioglossum vulgatum and Botrychium ternatum (the only 
members of the Ophioglossaceae the roots of which were seen) no 
trichomes could be found. 
The available species of the family Schizaeaceae were exceptional 
amongst the Filices examined in bearing trichomes of the second 
type. This case will be described below. 
Hydropterideae. 
Marsiliaceae : Afarsilia quadrifolia, AT. (uncinata ?). 
In Azolla, the epidermis of the root has a somewhat complicated 
development, which is fully described below. Salvinia is without 
roots, if we except the transitory root of the sporeling, which I 
have not seen. 
Monocotyledons. 
In a large number of Monocotyledons the hairs are borne by 
special cells predetermined at an early stage, in the manner to be 
described below. The Liliiflorae, however, with but slight excep¬ 
tion, the Spadiciflorae in the main, and numerous examples from 
other subdivisions of the Monocotyledons, present trichomes of the 
first type only. The species in which I have determined this to be 
the case are the following : — 
