Endosperm with micropylar Haustorium

A very prominent and aggressive micropylar haustorium is seen in Impatiens. Here the division of the primary endosperm nucleus is followed by a transverse wall, to form an upper smaller chamber and a larger lower chamber. The terminal/distal part of the upper chamber develops into an extensive, much branched haustorium. Its branches extend deep into the funiculus and derive nutrition. Micropylar haustoria are present in many other plants such as Nemophila and Hydrocera.

Figure: LS. Upper part of ovule of impatiens showing endosperm with micropylar haustorium; note the penetration of branches of the haustorium into tissue of funiculus.