Anii.vA 123 



In .1% KH-POi. Rather short, hut very stout growth. A gootl nuiiil)LT of larj;c and 

 irregular and often branched sporangia, forming very many spores, and some generally 

 remaining inside. The spores on emerging do not stick to sporangium, but fall to 

 bottom in open order. 



In .1% XaH2P04. Strong and very stout growth. A good many large sporangia, often 

 irregular and with more than one mouth, usually some spores remain inside. Many 

 oogonial initials, most of which were smooth, but some spiny; none matured eggs. 

 Some of the hyphae had a diameter of g(y^. Some of the large threads were segmented 

 up into dense, rather short fragments. 



In .1% K5S04. About I inch growth. Hyphae very strong, as in preceding. Xo sijor- 

 angia. A number of oogonia, but no good eggs maturing. 



In .1% Ca3(P0j):. About l inch growth. \'ery large hyphae. Immense number of 

 oogonia, with 1-3 or 4 eggs each. Sporangia present, but not numerous. The great 

 majority of the oogonia were quite spherical and without spines. Some, howe\er, 

 had distinct and even numerous spines. More large oogonia with 4 eggs than before 

 seen. 



In .1% Ca(N03):. Stout growth, but not so extensive as in others. Almost no sporangia. 

 Many oogonia remarkable for their very long stalks, 2, 3 or 4 times longer than usual, 

 giving the culture a very peculiar appearance. The stalks massive, simple and straight. 

 A good many good eggs formed. 



In .1 % KjPO<. Xo growth. 



On corn meal agar. Growth vigorous, covering dish. Many enlarged and denser ends oi 

 stout hyphae becoming cut up in rows of sections to form gemmae. Locally there were 

 found also a good many oogonia of perfectly normal appearance and with I or 2 good 

 eggs, almost all spiny. 



The following experiments were made to test the best method of 

 preserving Hve cultures: 



Culture put in vial on corn meal agar, vial closed with a plug of cotton and placed in a 

 dark chamber in May, 1913. When tested in December, 1913, it was found to be 

 alive. 



Culture put in distilled water Xovember 18, 1909. When tested on September 22, 1917, it 

 was found to be dead. 



13. Achlya apiculata deBary. Bot. Zeit. 46: 635, pi. 10, figs. 3-5. il 



Plates 42 .\xd 43 



\'cgetative growth ample and abundant, but not so stout as in 

 A. oblongata or in the Prolifera group. The main filaments mostly about 

 4(>-6oyL thick, tips rounded; breaking up soon after maturity into seg- 

 ments with little or no change in the appearance of the threads, each 

 segment becoming a gemma and resting indefinitely until the condi- 

 tions change, then forming spores like sporangia. Sporangia moder- 

 ately plentiful, long or short, usually somewhat larger than the threads 

 and gradualh' pointed towards the end, emptying as usual for an Achlya, 

 or often remaining closed and emptying as in Dictyuchus. Spores cili- 

 ated on emerging and capable of swimming under certain conditions 

 (see notes under experiments), 12.5-14.5;^ in diameter or at times larger. 

 Oogonia not formed regularly or aljundantly except at low temperatures, 

 racemosely borne on the tips of short or rather long branches which 



