VOLUME LVI NUMBER 1 
TFL 
BOTANICAL GAZETTE 
JULY 1913 
THE LIFE HISTORY OF ZANARDINIA 
CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY 174 
SHIGEO YAMANOUCHI 
(WITH TWENTY-FOUR FIGURES AND PLATES I-Iv) 
This paper deals with nuclear conditions in the life history of 
Zanardinia collaris Crouan, a monotypic genus which with the 
genus Cuileria constitutes the Cutleriaceae. Zanardinia is peren- 
nial and, like Cutleria, is characterized by large motile spores, whose 
formation is limited to a very short period of the year. On account 
of the shortness of this period and the consequent difficulty in 
getting reproductive stages, it was described as a species of Zonaria 
(AGARDH 1) belonging to the Dictyotales, but was placed in the 
Cutleriaceae under its present name when CRovaN discovered that 
it had gametangia identical with those of Culeria. 
Since AGARDH (1), several authors, including DerBrs and 
SOLIER (7), CRoUAN (4), JANCZEWSKI (11), and SauvaGEAu (15), 
have described the outer morphology of the creeping and coriaceous 
thallus of Zanardinia and its multiplication by proliferation from 
the surface; and it must be admitted that some of these authors 
confused the young Zanardinia with immature stages of Cuileria 
adspersa, the two forms being confusingly alike in the juvenile 
condition. 
REINKE (13, 14) was the first to describe the reproductive 
structures of Zanardinia. He observed, working at the Naples 
Station in 1875-1876, the actual fertilization of the female gametes 
by the male gametes. There seemed to be no apogamous germina- 
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