On the Structure of the Haustoria of some 
Phanerogamic Parasites. 
BY 
GEORGE J. PEIRCE, S. B. 
With Plates XIII, XIV, and XV. 
HE work, the results of which are given in the following 
X pages, was undertaken at the suggestion of Professor 
Eduard Strasburger, and performed under his supervision. 
Five species of Cuscuta have been studied. The material of 
Cuscuta americana , L., was collected by Dr. Fr. Johow in 
1883 on the Island of Grenada in the West Indies. It con- 
sisted of well-grown specimens of the parasite, some in flower, 
others younger, others older, and considerable quantities of 
the host-plants, all preserved in strong alcohol and in 
excellent condition for histological study. The material of 
three of the other species, C. epilinum , Weihe, C. epithymum , L., 
C. glomerata , Choisy, was grown in the Botanic Garden of the 
University at Bonn and preserved in alcohol. C. europaea , L., 
the last species studied, was found growing wild, and was 
also preserved in strong alcohol. I regret to say that all the 
material of the same species was collected at one time, and 
that for this reason interesting questions as to the changes 
which may take place in these parasites growing in temperate 
regions, as the season when life is possible draws to a close, 
cannot now be answered ; but I hope in a subsequent paper 
[Annals of Botany, Vol. VII. No. XXVII. September, 1893.J 
