THE COMMON PRICKLY SHIELD FERN. 131 
at least of them (lobatum) has been distinguished as a species by 
various authors; and another, Zonchitidoides, has been sometimes 
regarded as a distinet variety, sometimes as the young state of 
lobatum. We are of opinion, that /obatum may be considered as a 
variety of aculeatum without violence to nature; and that Zonchiti- 
doides, rather than a distinct variety, is the partially developed or de- 
bilitated condition of Jobatwm, whether caused by youth, age or star- 
vation, or any other depressing influence. The two are certainly not 
permanently distinct, but interchangeable, for cultivated plants of 
lonchitidoides may be nurtured onwards into lobatum proper, and 
lobatum may be starved back into Jonchitidoides. The plant to 
which the latter name is given, is a dwarf, simply pinnate, fertile 
form, often very much resembling P. Lonchitis, but less spiny, 
not imbrieated, and with a greater or less tendency to become 
lobed. The species has occasionally been. found with the apex 
multifid and the pinne dichotomous; and sometimes has been 
known to produce bulbils in the axils of the lower pinne; but 
these variations are accidental. The more marked varieties are :— 
1. lobatum (Deak.). This variety is doubtless a more fully de- 
veloped condition of the lonchitidoid form above mentioned. It 
has narrow lance-shaped fronds, one to two feet long; these are 
subbipinnate, i.e., a few only of the pinne develope pinnules. 
The anterior basal pinnule is always distinct, considerably enlarged, 
and strongly auricled; but the rest of the pinnules are either 
decurrent or confluent, and not auricled. The type form of the 
species is broader, and most of its pinnules are distinct and 
auricled, and between this and the variety Zobatum, there is to 
be found numerous intermediate grades; but yet our experience 
does not tend to the conclusion that the marked forms of lobatum 
can be made to develope into aculeatum by culture, but on the con- 
trary, that it is a permanent variety of which various gradations 
exist in a natural state. [Plate XVII A.—Folio ed. t. X1.] 
This plant (var. lobatum) is by no means uncommon, as will appear 
from the following recorded habitats :一 
Peninsula.—Devonshire: Totnes; Barnstaple; F. Mules; Challa- 
K 2 

