SPIROGYRA 197 



United States: Texas, Karnac, April 27, 1938. 



In this collection the outer spore wall was much larger than the median 

 wall. 



179. Spirogyra taylorii Jao 1935. Trans. Amer. Micros. Soc. 54, 



p. 4, PL I, Figs. 2-3. 



Vegetative cells 12-16(1 x (48-) 70-193 ju,, with plane end walls; i 

 chromatophore, making 2.5 to 6 turns in the cell; conjugation scalar- 

 iform; tubes formed by the male gametangia; fertile cells inflated 

 toward the middle and usually more on the conjugating side, up to 

 33 /-i; zygospores ellipsoid, 19-29;". x 39-45 /x; median spore wall finely 

 reticulate to punctate, yellowish-brown at maturity. (PI. XXXIII, 



Fig- 9-) 



United States: Massachusetts, Woods Hole. 



The fertile cells are continuous in the filaments, not separated as in the 

 next species. Named for W. R. Taylor, University of Michigan, author of 

 Marine Algae of the Northeastern Coast of North America and many con- 

 tributions to both fresh-water and marine phycology. 



180. Spirogyra liana Transeau 1934. Trans. Amer. Micros. Soc. 



53, p. 228. 



Vegetative cells 11-16/J. x 75-160/^1, with plane end walls; i chro- 

 matophore, making 2 to 6 turns; conjugation scalariform and lateral; 

 tubes formed wholly by the male gametangia; inflated single or paired 

 fertile cells usually separated by i to 5 nonconjugating cells; zygospores 

 ellipsoid, 23-^0 m x 35-50 m; median spore wall yellow, smooth. (PI. 

 XXXIII, Figs. 1(^11.) 



China, Szechwan and Kiangsi; Sweden. 



Named for Liang Ching Li, Fan Memorial Institute, Peiping, China. 

 This is one of the smallest of the species with plane end walls in which the 

 conjugating tubes are formed by the male gametangia. In most of these 

 species (Nos. 177 to 197), the conjugating cells are arranged singly or in 

 pairs with one to several intervening nonconjugating cells. At the inception 

 of conjugation, food substances accumulate in these gametangia and they 

 become darker green and filled with starch grains. At the same time the 

 intervening cells become lighter green and the chromatophores become 

 thinner and narrower. This group of species may be designated the "punc- 

 tata group" after the first of these species to be described. 



S. hydrodictya (No. 177) has these same characteristics and has in 

 addition the compressed-spherical spores characteristic of the "majuscula 

 group" of species. This species illustrates one of the difficulties in the path 

 of anyone who attempts to subdivide the genus Spif-ogyra on the basis of 

 tube formation or spore form. 



Among the replicate species of Spirogyra there is a corresponding group 



