Coker: Two New Species of Water Molds 
295 
positively for Achlya caroliniana. In this case if the sporangium is 
put on the slide in a very thin layer of water the spores will swim 
slowly apart on emerging and scatter themselves over a limited 
area near the mouth of the sporangium. By addition of iodine 
solution the cilia were clearly seen. In the case of Achlya De 
Baryana 11 I have recorded the occasional breaking up of the 
spore mass into scattered groups, but I have not seen any swim- 
ming motion in that species. Humphrey in his monograph also 
demonstrated the presence of cilia on the escaping spores of 
Achlya americana. It will be noted, however, that in none of 
these cases do any of the spores swim away regularly and under 
ordinary circumstances. In this respect Achlya paradoxa is 
unique. 
In case of bacterial contamination, or foulness from any cause, 
or where the parts are put in liquid nutrient media, there is strong 
tendency for the spores to be retained in the sporangium, or if 
discharged for them to sprout at once without a second swimming 
stage. There has arisen a loose way of speaking of all sporangia 
when the spores are retained, or even in part retained, as “ Dictyo- 
sporangia ” a term that should be used, only when spores emerge 
through the wall of the sporangium and escape for (what is 
homologous with) the second swimming stage. As one might 
expect, there is variation in Dictyuchus itself in this respect, the 
spores frequently sprouting by the A planes method (see below). 
Variations in the discharge and behavior of the spores are re- 
corded in the following cases : 
Achlya aplanes Maurizio: Flora 79: 109. 1894. The behavior of 
the spores in this case is very peculiar. There is no swimming 
stage, the spores on emerging sprouting into tubes. Frequently 
they do not emerge at all, but remain in the sporangium and 
sprout there. 
Achlya caroliniana Coker: Bot. Gaz. 50: 381. 1910. The spores 
may be retained and sprout as in Aplanes, or under certain cir- 
cumstances may emerge in a motile condition. 
Later observation by me shows that under certain conditions 
as an egg yolk in 1 per cent. KN 2 P0 4 the spores may not stick to 
the sporangium mouth, but fall to the bottom in open order. 
11 Mycologia 4: 319. 1912. 
