ACHLYA 147 



Achlya ccntorta Cornii. Ann. Sci. Nat., Scries 5, 15: 2S. pi- '. tiK^- 10-15. 1872. 



Like the above this is 50 nieagerl\ described as to be iiKlelinablc. Oogonia smooth, 

 borne on long, spirally twisted branches with odd-lookint.'. local ouli;r()\vths; eggs averag- 

 ing 8 in an oogoiiiiuii; antheridia cylindrical, branched [compare .1. proliferoides]. 



Achlya dioica Priii^sheim. Jahrb. f. wiss. Bot. 2: ;;ii, pi. 23, figs. 1-5. i860. 



This is a name given to a lot of hyphae of an Achlya without oogonia, and attacked by 

 W'oronina polycyslis. It has no validity. 

 Achlya penetrans Dimcaii. Proc. Roy. Soc. London 25: 2,vS. 1876. 



This is probably a Siphnnaceous alga, as Humphrey thinks. 

 Achlya oidifera Horn. .\nn. Myc. 2: 231, fig. 20. 1904. 



The following is adapted from the original: 



Growth good on llief, mealworms, etc., and in pea extract, h\phae about 451A thick 

 in the latter medium; sporangia and zoospores produced in abundance, but oogonia nearly 

 always absent — not formed in numerous cultures on various media, such as agar-agar, 

 haemoglobin, leucin, and numerous other media that easily produce oogonia in Achlya 

 polmndra and Sapmle^nia mixta; oogonia formed only once and then in the inside of an 

 ant pupa. They were spherical, vaiied in size, and had numerous pits. Eggs 2-8 in an 

 oogonium, and with fat-droplets on one side. Antheridia not ob?er\ed with certainty as 

 the oogonia were too old when found. The egg-like gemmae [oidienartiger Zerfall] pro- 

 duced in chaint (hence the name), and forming spores when brought into pure water: cap- 

 able of growth after a long rest (over a month) as in other species. 



The author suggests that on account of the formation of eggs inside the substratum 

 this species may represent a transition towards the Peronosporaceae, and that only in cer- 

 tain peculiar conditions not yet understood will eggs be produced. 



From the abo\-e it will be seen that this species is insufficientK- described and in need 

 of further study. It must be considered doubtful, as Minden remarks. 



Achlya ocellata Tiesenhausen. .Arch. f. Hydrobiologie und Planktonkundc 7: 287, fig. 14. 



iqi2. 



"Turf stifT, not thick. 3 nmi. broad, main threads up to 175(1. thick at base. Sporangia 

 as usual. Oogonia raeemosely borne on the more or less thickened hyphae. Stalks rarely 

 up to 62(1 long, mostly shorter than the diameter of the oogor.ia, at times absent with oogonia 

 sessile or intercalary; oogonia 40-1180. thick, spherical, rarely pyTiforni. wall smooth with 

 evident pits of medium size. Eggs 17.5-25(1 thick, with a snidll brightly refractive oil 

 drop that is ver>' characteristic, 5-20 or more in an oogonium, 01 rarely one. Antheridia 

 on branches 5-8(1 thick, which are androgynous or diclinous from nearby threads." 



Found near Campfer, Oberengadin, Switzerland. Another form found near the same 

 place had very short oogonial stalks, otherwise like the first. 



The author states that the species is very near A. americanu but differs in the some- 

 times diclinous antheridia and in the peculiar shining drop'et in the eggs which is very 

 different in appearance from the eccentric egg of A. americana. \s the author does not 

 mention any other member of the Prolifera group and gives no evidence of having seen 

 any other of them it seems more than likely that he makes all this ado over the typical 

 eccentric egg of the group. From his figure and description it is probable that his plant 

 is A. americana. 

 Achlya Nowickii Raciborski. Sitzungsber. d. Krokaner .\kad. d. wiss. 14: 149-16S, pi. 3. 



1886. 



We have not seen the original, which is in Polish, and take the following from Minden 

 In Kr\()t. Fl. Mark H. 5: 55.3. 19 12. 



