ee 
- 
Mém, 
1904] COULTER & CHRYSLER—REGENERATION IN ZAMIA 453 
anatomical limitations of this reproductive power, by artificial mutila- 
tions of various kinds, but probably the proper conditions for vigorous 
growth were not maintained; at least no results were obtained. 
We have found no record of this behavior of Zamia, except in a 
statement made by WILLDENOow,’ a century ago, of which the follow- 
ing is a translation: 
The majority of palms die as soon as their trunk is cut or even damaged. 
There are only a very small number of them which, like Chamaerops humilis and 
Rhapis flabelliformis, send out from their root new shoots; and Cycas circinalis 
_ is the only one which sends out shoots from its trunk when this has been cut; 
further, the stem of this tree gives out new roots where it finds itself in contact 
with the soil. The different species of Zamia may be cut up and thus multiplied 
artificially by cuttings, but with the exception of Cycas and Zamia no other p 
survives amputation of the stem. 
This power of producing new shoots and roots after mutilation 
ls usually called “regeneration,” but this term seems to have been 
applied primarily rather to the restoration of lost parts than to the 
production of a complete new structure. As a consequence of its 
broader application, there has been a tendency to regard the regenera- 
tion ordinarily observed in plants and in animals as of two distinct 
inds; the former being nothing more than adventitious budding, 
the latter actual restoration of lost parts, the new structure becoming 
an integral part of the old. The great majority of the illustrations 
of regeneration in plants are cases of adventitious budding rather 
than regeneration in the stricter sense. We recognize the fact that 
the whole subject of regeneration among plants is in an inchoate 
Condition, but perhaps the two kinds cannot be distinguished by any 
_ €xact definition. Most of the cases presented in this paper are not 
Tegeneration in the restricted sense defined above, but in addition to 
_ Adventitious sprouting in Zamia there also seem to be cases of direct 
*estoration of lost parts. 
In the mutilated (mostly decapitated) stems of Zamia studied, 
the new shoots arise most frequently from the vascular part of the 
Central cylinder, as many as five shoots having been observed to 
Spring from this region in a stem 3 °™ in diameter, though only one 
t may occur. The vascular elements present in these shoots 
*WILLDENow, C. L., De quelques nouveaux palmiers de V Amérique méridionale. 
Acad. Roy. Berlin, 1804, p. 20. 
