FRUCTIFICATION HY ZYGosi'OKE.S. ,7 



siriuilUiieously .swelliiif,' up in the simpe of a cliih tMiitiiining a 



foMsidoniblo accuimilatioii of pliisuiii. As soon as tin- i-UiU of 



t\w two liypli:.' c-onif into coiityict (i) thev flatten an<l an inttM-- 



growth of tla' nieniljnincs occurs at tliis sjrnt, whercujion a senium 



isilevelo|)C(liin*acli of tin* 



clubbed enils, wliich are 



therein- sepaiated from 



their respective hy})h;e. 



Each is thus ilividt'd into 



two parts : a terminal 



cell, to whicli the liainc 



copulation cell oi gamete 

 is given (2 a), and an 

 interior cell, or suspensor 

 (2 b) supporting tiie 

 gamete. The partition 

 wall between the two 

 terminal cells is then 

 absoil)ed, and the con- 

 tents of these latter fuse 

 to form a new, uniform 

 structure: the zygospore 

 or zygota(3 </). At lir>t 

 the outside still continues 

 to present the appear- 

 ance of two cells, but the 

 contour soon become.^ 

 idiuided otT. The mem- 

 Inane thickens ami ex- 

 hibits a sepanition into 

 an inner (endosftorium) 

 an<l an outer cjise (exo- 

 sporium), the latter turn- 

 ing very dark in colour 



Via. K.I. — MiK-or iiiik-ihIo. 

 Korniatlon of the /.yi;i>«iK.>re8. 



1. Twt) liy|ihii- ill ttTinliinl ooiitncU 



2. ArlicuUtioii into kkiiicU- n and siisiH-iiftor 6. 



3. KuBJonoftheKanictt-sd ; the nii>in)>riiiu- tliickms. 



4. Kii>e zypisiwire h gu|>]M.>rU->l l>y the guspcn&tirs 

 a (I. (Ma);ii. "f i .«, .■.■>.) 



5 lieriniiintioii ot tlic zygospore to a spuranifiuni 

 .Mll^'n. almut Oo. (After Brtjfld.) 



stoni. 



t)f accumulated nutrient 



and becoming lumpy or 



waity on the outside. 



iiie cell contents siu'- 



rounded by the endo- 



sporium contain large quantities 



mati'rial. 



Sooner or later tin- zygospore becomes detached from the 

 suspensors, and then leads a separate existence, lieing a resting 

 cell it can, if neces.sjiry, remain (piiescent for a consi<leniblo time, 

 and then germinate mi the recurrence of favounible external 

 conditions. 



The production of zygospores in the manner ju.st descriluHl 

 has been regarded by some mycologists as a sexual process; whil.st 

 other workers contest the admissibility of such an hypothesis, 

 vol.. 11. It 



