I02 THE SAPROLEGXIACEAE 



13. Antheridia both androgynous and diclinous; oogonia with a single apiculus; eggs 1-5 



in an oogonium, large, averaging about 36|U thick A. apiculala (13) 



13. As in A. apiculata except eggs usually 1-2 and oogonia smaller 



A. apiculata ^•ar. proUfica (14) 

 13. Antheridia both androgynous and diclinous, oogonia usually with several blunt papillae; 

 eggs 4-8 (seldom up to 12 or more) in an oogonium, small (15-25^) 



.4. oUgacantha (p. 144) 



13. As above, but eggs usually about 10 (1-25), 22-27M thick; papillae more numerous, 



and oogonial stalks recurved above -4 . recurva (p. 144 ) 



13. Antheridia all or almost all androgynous 14 



14. Antheridia often arising from a hypogynal cell; eggs commonly 3-5 in an oogonium, 



averaging 27-28M thick ^4. hypogyna (i) 



14. Antheridia not formed as above I5 



15. Eggs commonly one or rarely two or three in an oogonium 16 



15. Eggs commonly 4-6 in an oogonium, averaging 25m thick A. papulosa (4) 



15. Eggs commonly 1-4 in an oogonium averaging 30-37^ thick .4. colorata (3) 



16. Oogonium densely covered with sharp spines; eggs one, rarely two or three, commonly 



34-36.5M thick A. radiosa (p. 139) 



16. Oogonia covered with sharp or blunt spines, mostly barrel-shaped with a large apical 



point ^- spinosa (p. 138) 



16. Oogonia covered with blunt warts, roughly spherical and with a distinct point; eggs 



one or rarely two, averaging about 20m thick A. glomerata (20) 



I. Achlya hypogyna Coker and Pemberton. Bot. Gaz. 45: 194, figs. 

 1-6. 1908. 



Plates 29 and 30 

 Hyphae slender, tapering gradually toward the apex, at base about 

 35ii. in diameter, at or near tip about 8;j., in vigorous cultures reaching 

 a length of i cm. Sporangia rather plentiful or few, nearly cylindrical, 

 a little larger at the rounded and papillate distal end, usually curved, 

 somewhat like those of Protoachlya paradoxa; dictiosporangia common, 

 sometimes more abundant than the typical sort; spores on emergmg 

 ciliated, a part usually dropping to the bottom and showing a little mo- 

 tion from the sluggish cilia. Gemmae at times abundant, again few, 

 pyriform or flask-shaped, less often spherical, often in chains of two, 

 three or four; long, rod-shaped gemmae are also formed by segmenta- 

 tion of the hyphae. Oogonia generally borne on short branches, race- 

 mosely arranged on the main hyphae, but occasionally terminating a 

 main hypha, and very rarely intercalary; globular or rarely oblong, the 

 walls not pitted, more or less abundantly producing short or long rounded 

 outgrowths, or a varying proportion smooth; yellow when old; diameter 

 26-83(x without the papillae which are up to 301J. long, the longest at 

 times on the smallest oogonia. Eggs 1-7 (commonly 3-5), centric, 

 diameter 20-361J., averaging 27-2811.; not rarely elliptic and then up to 

 45 X 57ii.. Antheridia cut off from oogonial branches justbelow the 

 oogonia, very rarely absent; simple antheridial branches with one or 



