ANNONA SERICEA AND ITS ALLIES, 
By Wiuturam E. Sarrorp. 
INTRODUCTION. 
In continuance of his studies in the Annonaceae, the writer finds 
that the silky annona of French Guiana (Annona sericea Dunal) is 
the type of a natural subgroup of the genus Annona, which should be 
segregated as a section. This will be composed of at least ten 
species, several of which have not hitherto received names. In 
addition to defining the section and characterizing the species, it has 
been possible in this paper to present photographs of a number of 
the type specimens, including that of Annona echinata and the flower 
of A. sericea, described and figured by Dunal in his classical mono- 
graph of the Annonaceae. For the photographs of the latter, the 
types of which are in the De Candolle Prodromus Herbarium, the 
writer is indebted to M. Augustin de Candolle. For that of A. trini- 
tensis he is indebted to the Director of the Royal Gardens at Kew. 
The remainder of the photographs, including those of A. spraguen, 
A. holosericea, and A. jamaicensis were taken in Washington under 
the writer’s direction. 
The accompanying drawings were made by Mr. A. B. Boettcher 
and Mr. J. M. Shull, those of the essential ‘parts being reproduced 
from camera lucida drawings of the writer. 
SYSTEMATIC TREATMENT. 
The species here described form a fairly well-defined genus sec- 
tion, for which the name Pilannona is proposed, to give it coordi- 
nate rank with the sections Euannona (based upon Annona muricata 
L.), Atta (including Annona squamosa, A. cherimola, and their 
allies), lama (based upon A. diversifolia Safford), Annonella (based 
upon A. globiflora Schlecht.),1 and Chelonocarpus (based upon A. 
scleroderma Safford).2 As in other natural plant groups there are 
1See Safford, W. E. The Genus Annona: The Derivation of its Name and its 
Taxonomic subdivisions. Journ. Washington Acad. Sci. 1: 118. 1911. 
2 See Journ. Washington Acad. Sci. 3: 103-109. 1913. -_ 
