14 IOWA STUDIES IN NATURAL HISTORY 
of the Compositae; Balicka-[wanowska (1) investigated numer- 
ous of the Scrophulariacee, recording several cases comparable 
to that found in Utricularia, particularly in Scrophularia ver- 
nalis which has both micropylar and antipodal outgrowths; 
while Merz (7) and Kamienski (5) worked on various species 
of Utricularia, outlining quite fully the story discussed in detail 
above. Of special interest is the paper by Lang (6), which re- 
sulted in shifting Polypompholyx and Byblis from the Droser- 
ace to the Lentibulariacee. Many of the figures of Polypom- 
pholyx in this paper are very similar to conditions found in 
Utricularia vulgaris. 
Antipodal outgrowths may be quite large, especially in the 
case of those ovules with massive integument, and some of them 
may attain to remarkable length and complexity. The antipodal 
region borders on a mass of tissue, merging into the funiculus, 
and makes connection quite directly with the major vas- 
cular supply of the ovule. This invites specialization in this di- 
rection and the question might well be considered as to why such 
haustoria are not more common and more highly specialized than 
they seem to be. In Utricularia the antipodal haustorium is 
post-fertilization in development and is purely an endosperm 
outgrowth, seemingly to tap the foods stored or transported in 
the epidermis of the ovule. Its importance diminishes relative- 
ly as embryo development proceeds, its work being supplemented 
and later supplanted by the haustorium at the opposite end of 
the ovule. 
In the closely related Polypompholyz, Lang (6), finds that 
the female gametophyte begins an antipodal haustorium which, 
as in the case of Utricularia, is later markedly developed by the 
endosperm, two cells of which dominate its growth. In Poly- 
pompholyx, however, there is developed an extensive nutritive 
tissue into which the haustorium enters so that it does not reach 
the epidermis of the ovule. The antipodal haustorium in this 
form is larger and functions longer than in Utricularia. 
While micropylar haustoria are not uncommon, these in gen- 
eral are smaller and less highly specialized. The explanation 
for their failure is not far to seek, since it follows from the re- 
lations of the embryo-sac to adjacent parts in this direction. 
