No. 625] HYBRIDS AMONG SPECIES OF SPIROGYEA 119 



When the reduotion division takes place these factors are 

 segregated in various combinations in the final spore 

 nucleus. 



7. AVlien the filamonts derived from liyhihl zygospore^ 

 fruit their ]iyl)rid diai-nct cr Im'couics evident iu tlie dimen- 

 sions of the filament, the clmra.-ter of the .^poi-iferous cell 

 and the form of the zygos]>ores. 



8. Inheritance is matriclinal and therefore the segrega- 

 tion becomes evident in the first generation. 



LITERATURE CITED 



Bessey, C. E. 



1887. Freshwater Alga? of the United States. P. 218. Plate 



CXXXVIII, Figs. 5 and 6, and CXLII, Figs. 5 and 6. 



1898. Observations on the Conjugatse. An7ials of Botany, 12: 43; 

 Plate V, Figs. 70 and 71. 

 Andrews, F. M. 



1911. Conjugation between Two Different Siiecies of Spirofi}ira. Bull. 

 Torrey Botanical Club, 38: 299. 



Overton, E. 



1888. fiber den Conjugationsvorgang bci Spirofiyra. Bo: d. Daitsrh. 



Botan. Gfn., (5: C8-72. 



Klehbahn, II. 



1888. Uber die Zygosporen einiger Conjugaten. Bcr. deutseh. Botan. 

 Gen., 6: 160-166. 



