INTRODUCTION 7 



We ha\-c found in Aclilya caroliuiana, A. proliferoides, A flagellata 

 and .1. Klebsiana that sporangia may open and discharge spores 

 through more than one papilla. This tendency is most distinctly 

 shown in the last species, which see for other peculiarities in 

 abo\-e hcha\-ior. 



Achlya hypogyiia. Spores ciliated on emergence and may show a sluggish 

 motion. See p. 102. 



Protoachlya and Isoachlya. For the behavior of the spores and spor- 

 angia in these genera, sec our treatment. 



Tbraustotheca clavata (deBary) Humphrey: Weston ('18, pi. 4, fig. 31) 

 shows the spores sprouting as in Aplanes. 



Dictyiichus movosporus Leitgeb ('69). In plate 23, fig. 8, Leitgeb shows 

 a sporangium with spores sprouting after the manner of Aplanes. 

 This variation I have many times seen in Dictyiichus sterile, which 

 is common at Chapel Hill (pi. 52, fig. 4). Weston ('19, pi. 23, fig. 

 18) shows a similar case in a sterile Dictyiichus. He also finds that 

 a spore may in some cases emerge from its cyst in the same form and 

 swim again ("repeated emergence"). 



Aplanes androgyniis {Archer) Hum'phrey. See our discussion of this spe- 

 cies. 



Aphanomyces stellatus deBary: Sorokine ('76). In plate 7, figs. 10 and 

 18, are shown sporangia discharging their spores in the exact manner 

 of Dictyiichus. Sorokine also shows sprouting at the mouth of the 

 sporangium, and sporangia with spores in more than one row. See 

 also Humphrey ('92, p. 79) for omission of second swimming stage. 

 We find that spores retained in the sporangium may sprout as in 

 Aplanes. 



Leptomitus lacteus (Roth) Agardh: Humphrey ('92) says on p. 136: 

 "While the zoospores ordinarily escape from the sporangia, they 

 sometimes become encysted within them (fig. 117). It is this 

 fact, probably, which led Braun to state ('51) that the spores of 

 Leptomitus are arranged in a row in the spore cases, and that no 

 acti\-e gonidia seem to occur." We ha\-e often seen some of the 

 spores retained. 



Apodachlya pyrifera Zopf ('88). The spores normally encyst at the 

 mouth of the sporangium and then emerge for a swimming stage as 

 in Achlya. Howe\er, they may, on occasion, swim away in emerg- 

 ing, or they may encyst in part in the sporangium. In our form of 

 the species it is much more usual for the spores to swim at once on 

 emergence. 



Monoblepharis macrandra Woronin ('04). In this species some or all 

 of the spores may be retained in the sporangium and sprout there. 

 Normally the spores on emerging show amoeboid movements. 



