22 
BULLETIN 1195, U. S. DEPARTMENT OF AGRICULTURE. 
Table 3. — List of potato varieties studied, showing the class to which each is assigned 
with respect to the condition of its anthers and pollen and to its ability to produce seed 
balls — Continued . 
Class with respect to- 
Variety or species. Source. 
Condition of 
anthers and 
pollen. 
Ability to pro- 
duce seed balls. 
1 
2 
3 4 A 
B C 
D 
Wild species — Continued. 
United States 
1 + 
1+ 
1+ 
1+ 
1+ 
1+ 
1+ 
1+ 
1 + 
1 + 

:::::::: 
I 
A® 
...... 
Solanum fendleri No. 11-12 
Solanum fendleri No. 11-13 
Solanum fendleri No. 11-14 
do 
...... 
.. :;: 
do 
do 
A© 
----,---- 
3 
...:; 
1 + 
1 + 
Solanum jarnesii No. 3-7 
do 
do . 
1 

Solanum jamesii No. 4-2 do 1 1 
Solanum jarnesii No. 4-4 do 1+ 
............. 
A® 
:::::::: 
— i 
A® 
:::::::: 
1+ 
14- 
A® 

Solanum jamesii No. 20 do 1 + 
Solan urn jamesii No. 21 do 1-f 
....!.. ...... 
Solanum jamesii No. 25 do 1 + 
Solanum ]amesii No. 26 do ', 1+ 
■ ■ *" 
i 
Solanum jamesii No. 28 1 do 1-4- 
Solanum jamesii No. 29 j do ; 1+ 
A® 
........ 
do ' 1+ 
Peru i 

Solanum maglia N o. 1-1-1 
2 
2- 
2 
Solanum maglia No. 1-3-1 
Solanum maglia No. 1-1-2 
Solanum maglia N o. 2-1-2 
do 
do 
do 
do 
2- 


S. fendleriXS. chacoen.se (Fi hybrid). 
Nos. 126-1, 126-2 ." 
Nos. 126-3, 126-5. 
United States . . . 
3 
3 
3 
! 
do 
do 
do 
do 

........ 
Nos. 126-7, 126-8. 
......... 3 
j 
Nos. 126-9, 126-10-. *. 
:::::::: 
:::::::: 
Nos. 126-11, 126-12 
Nos. 128-13, 126-17 
do 
do 
:::::::: ;! :::: 
Nos. 126-18, 126-19 
Nos. 126-21,126-22 
Nos. 126-24, 126-26 
Nos. 126-29, 126-30 
do 
do 
do 
do 
:::::::: 
3 
3 
! 
i 
.... 
.... 
Nos. 126 33, 126 34.. . .. do 
:::::::: 

Nos. 126-35, 126-36. . 
....do 
......... 
— — 
........ 
Nos. 126-38 
do 
Nos 126-40, 126-43 
do 
Nos. 126-50, 127-2. . * " 
.do 
3 

! 
STERILITY IN HYBRIDS. 
The only known hybrids between species of potatoes which up to 
the present time hare been studied for impotence are the first- 
generation plants of a cross between Solanum fendleri and S. chacoense 
grown at Presque Isle in 1922. These hybrids bloomed abundantly; 
the anthers were well formed, fully colored, normally dehiscent, and 
the pollen abundant. From one to six tests for germination of pollen 
for each of 29 plants were made, involving many thousands of grains. 
Plump pollen grains were very few in number, and only five short 
pollen tubes were seen. Tests of the pollen of the parent species at 
