— 435 — 



10. Achlya decorata sp. nov. ; cf. the diagnosis page 383. 



This species is closely related to Achlya racemosa. On a single 

 hypha I observed numerous typical ^decorata" oogonia, a single oogonium 

 witii characters of Achlya racemosa and an intermediate oogonium 

 resembling that of forma stelligera (fig. Ill e), without being exactly 

 similar to the oogonia of this form. This species indicates a stage of 

 further evolution of the membrane of forma stelligera. 



11. Achlya polyandra (Hildebrand) de Bary forma Americana 

 Humphrey. 



Humphrey (1893, pag. 116) has described a species Achlya Ameri- 

 cana from which the Achlya polyandra differs by the want of pores in 

 the oogonial membrane. It is this form I have met with by my investiga- 

 tions, but I cannot agree with him in setting up a new species, because 

 I have found variation in the number of the pores. 



Aphanomyces de Bary. 



In my cultures 1 have but rarely met with any species of this genus. 

 In Nature I have only with one exception found species of this genus on 

 the tegumenta of the nymph* of the Phryganeas ; cf. my paper in Jour- 

 nal de Botanique 1903. Most frequently vegetative mycelium occurs. The 

 tegumenta in question are common in Denmark from June to September. 



15. Aphanomyces scaber de Bary. 



This species I have only found in a single locality: in my earlier 

 paper (1903) I have indicated it as „assez commun". 



16. Aphanomyces coniger sp. nov.; cf. the diagnosis pag. 387. 



This species I have formerly (cf. my paper 1903) indicated as 

 Aphan. stellatus. 



18. Apodachlya pirifera Zopf. 



This species is very common in particular in the spring but occurs 

 generally only with zoosporangia. Apodya lactea has not been found, but 

 I have not examined such localities in which it occurs. 



20. Sapromyces Reinschii (Schroeter) Fritsch. 



When Thaxter (1896) writes with regard to the basal cell that „this 

 (is) resembling in all respects the segments of the filaments which arise 

 in small numbers from its apex", I do not agree with him. It is un- 

 doubtedly Sapromyces Reinschii I have examined, but the basal cell was, 

 as shown in Fig. IV, c, distinctly different from the segments of the 



