2 
Campbell—Studies on the Araceae. 
from the works of these investigators I have not been able 
to find any references to the embryonic structures in these 
interesting plants. 
The Araceae show many indications of being a primitive 
type, and this suggested a careful examination of them, in 
connexion with a general study of the development of the 
flower and embryo in the lower Monocotyledons, begun some 
time ago. The rich flora of Pacific America is unfortunately 
almost wanting in Aroids, so that except for Lysichiton 
Kamtschatcense , Schott, which is very common on the north¬ 
west coast, no material was available in California. A trip 
to Jamaica in the summer of 1897, however, gave me an 
opportunity to collect a number of forms, part of which 
furnished the materials for most of the present paper. 
Through the kindness of the Hon. W. Fawcett, Director of 
the public gardens, the fine collection in these was put at my 
disposal, and this, with the rich supplies furnished by the 
numerous native species, provided me with a large amount 
of material. Unfortunately, much of this proved to be of no 
value, as the flowers require great care, which it was not 
always possible to give, in preserving them for histological 
work. Moreover, at the time, the best methods of preparation 
were not understood, and thus much valuable material was 
lost. 
In the summer of 1898 a trip was made to Alaska, and at 
Sitka abundant material of the characteristic Aroid, Lysichiton 
Kamtschatcense , was secured. At this time, the last of June, 
the flowers were gone, but a good supply of the young fruit 
in various stages of development was secured. Through the 
kindness of Professor Charles Hill, of Seattle, younger flowers 
preserved in chromic acid had been sent me, so that I was 
able to make a fairly complete study of this species. 
On coming to England last summer, examination was made 
of the fine collections at Kew, and through the courtesy of the 
Director, Sir W. T. Thiselton-Dyer, permission was given me 
to avail myself of the plants growing there. I have thus been 
able to replace most of the spoiled material collected in 
