662 
Miyake . — The Fertilization of 
opposed this view, and maintained that in certain species 
he actually observed the fertilization taking place by the 
amoeboid swarmers — £ Spermamoebae 5 — developed in the 
fertilization-tubes and set free from them. His observations 
were objected to by Zopf (’82, ’83), De Bary (’83), Ward (’83 a) 
and others. 
Hartog (’89, ’91, ’95), Dangeard (’90, ’91), Humphrey (’92), 
and Trow (’95, ’99) studied the nuclear phenomena of this 
group. Hartog and Humphrey agree in the absence of 
fertilization, Dangeard leaves this question undecided, while 
Trow maintains that in certain species at least true fertilization 
.takes place. 
In the Peronosporeae, on the other hand, the true process of 
fertilization, i. e. the fusion of sexual nuclei, takes place in all 
the species so far studied. The results of De Bary’s (’81) 
classical researches, confirmed by the recent cytological 
investigations of Wager (’89, ’96, ’00), Stevens (’99, ’01), 
Davis (’00) and others leave no room for doubt on the exist- 
ence of fertilization in this group. 
The question naturally arises as to which of these two 
groups of Fungi Pythium is most closely related. Pringsheim 
(’58), who established the genus Pythium , placed it among the 
Saprolegnieae. Cornu (’7 2) in his monographic studies of 
Saprolegnieae, included Pythium in that group. Later, 
De Bary (’81) placed this genus under the Peronosporeae, 
and this arrangement has been accepted by later students 
of Fungi. More recently, Schroter (’93), in Engler and 
Prantl’s i Pflanzenfamilien,’ classified Pythium as a member of 
Saprolegnieae, placing it under the separate family Pythiaceae. 
The reason for adopting the new classification is given by him 
as follows: c Die Pythiaceae zeigen eine sehr nahe Verwandt- 
schaft zu den Peronosporineae, besonders in Hinsicht auf die 
Befruchtung und die Oosporenbildung. Sie sind darum auch 
von De Bary mit den Peronosporineae vereinigt worden. 
Habituell stehen sie den Saprolegniineae naher, und es 
erscheint in einem System, welches nicht mehr einsichtig 
auf ein eitizelnes Merkmal (die Sexualitat), sondern auf die 
