430 BULLETIN No. 127. [August, 



quality. We found varieties of all colors .. except the purple types 

 which were ol good quality. No purple skinned potatoes were 

 available which were of a size that indicated maturity and this 

 might account for the fact that they were of a poorer quality. 



2. Nature of skin. Those varieties which have a netted skin 

 were found to be generally smooth-skinned when immature. A 

 corky appearance indicated both maturity and a better keeping 

 quality. In some cases one end of the tuber had a corky netted skin 

 while the other end was smooth; these were generally different in 

 internal structure, indicating some obstruction to perfect develop- 

 ment. Very rough-skinned varieties as Russet and Scabproof were 

 in general less susceptible to infection with potato scab, but were 

 neither of better quality nor of higher starch content than other 

 varieties grown under the same conditions ; which is in opposition 

 to the conclusions of Krzymowski (63). 



Lenticels were found to be present in all sizes of potatoes and 

 were well developed in individuals of most varieties. A develop- 

 ment of strong healthy lenticels indicates maturity in the tuber al- 

 though a number of writers have pointed out that possibly scab in- 

 oculation takes place in them. 



3. Color of -flesh. White fleshed tubers are the only ones at 

 present accepted in the American markets and it may be that yel- 

 low flesh is correlated with a strong flavor and a poor quality 

 by our standard. A number of varieties with a yellow flesh im- 

 ported from France and considered by the French to be of prime 

 quality were tested and were gummy and hard after boiling. 

 These varieties are considered of good quality for frying and for 

 use in salads. 



4. Shape. Round potatoes as Noroton Beauty, and oblong 

 round potatoes as Early Ohio have both been found to be of excel- 

 lent table quality, but the general popularity and prime quality of 

 the round flat (as Irish Cobbler) and short-oval-flat types (as in 

 Carman's productions), seem to support Fischer's view that po- 

 tatoes of these types are better. The greater possible percentage 

 of cortical layer in these types seems to be sufficient reason for the 

 conclusion, but there is a further argument in the fact that salad 

 potatoes are usually small round types, or long slender types as the 

 Lady Finger. 



5. Depth and frequency of eyes. Great depth of eyes will be 

 avoided because of the waste in peeling. A number of writers 

 have also stated that extremely deep eyes tend toward coarseness 

 of the variety, and indeed this seems to be the case. The vital- 



