80 



10 per cent, thus indicating a very early maturity. The Valencia orange from Pomona 

 (No. 21) shows a decidedly lower sugar percentage [9.2 per cent], as does the con- 

 temporaneous Malta Blood from Riverside [8.8 per cent]. The St. Michaels shows 

 the lowest average of all the oranges (6.71 per cent), although the roundish sample 

 from Pomona falls only a little below 10 per cent. 



Comparing these data with those of previous years, heretofore published, we find 

 that the sugar percentage cf the Navel appears to have risen from 9.89 per cent to 

 10.80 per cent. For the Mediterranean Sweet the figure remains practically identical. 

 For the St. Michaels it is higher than we have found it this season. 



Acid in the Juice. — In respect to acid, we note at once the maximum in the Malta 

 Blood of over 2 per cent, with an average of 1.6 per cent in the three samples 

 examined. Thencxthighest figures occur in theearly samplesof Mediterranean Sweet 

 from Smartsville, a maximum of 1.G8 per cent; but the average of the May samples 

 from Riverside and Pomona is 1 .2'A per cent. The St. Michaels of Marysviilo, .January 

 22, shows the next highest maximum w ith 1.40 per cent, but iu the later samples of 

 April and May we liud in the Riverside sample (No. 14) a minimum of 0.84 per cent, 

 witii an averageof 1.07 for the four later samples examined. In contrast to the Malta 

 Blood, therefore the St. Michaels counts among the varieties of low acid, combined, 

 however, with rather a low sugar percentage, as stated above. 



The Valencia rates in nearly the same respect with the St. Michaels, while the Tan- 

 gerine shows the low figure of 0.87 per cent of acid, with, at the same time, a very 

 high sugar percentage. A former analysis showed for its close relative, the Man- 

 daiin, a lower minimum of acid (O.'.JG per cent), and the highest sugar percentage on 

 record — 13. .^4 per cent. 



The Navel justifies the statement, made in a former report, of the low acid percent- 

 age even in samples gathered as early as January and still more in those of later date 

 from Riverside and Pomona. The minimum of all (0.77 per cent) is shown by the 

 Pomona fruit (No. G), with, at the same time, the highest sugar percentage ( 11. 20)of 

 the series. In the aggregate the average acid jiercentage of the Navel is the lowest 

 of all, with the highest average of sugar (9.92 per cent), outside of the Malta Blood. 

 These data, together with its firm lle.sh, thin and buioothrind, and excellent keeping 

 qualities, sulliciently explain the great preference given it in our markets. 



Comparing the results obtained in ls91 with those iu previous publications of 

 this Department (1879-87) we note first an apparent increase iu the average weight 

 of the several varieties. We also find that while the percentages of rind show very 

 nearly the same average as iu 1891, there is a marked discrepancy in respect tojuici- 

 nesM, the pressed pulp averaging about 2'^ per cent less in earlier specimens. How 

 far these dilTerences may bo due to iulliiencesof season or accident in sampling is dif- 

 ficult to decide with the data before us ; the more so as the acid and sugar percentages 

 show very nearly the same absolute as well as relative figures. Increased age of the 

 bearing trees may possibly account for .some of these differences. • • • 



Nutritive values — nitrogen content. — The llesh-forming ingredients (albuminoids) of 

 any article of food being of great importance as regards its proper uses, it is of 

 special interest to compare in this respect the orange with other fruits, and the 

 dilVereut varieties of oranges with each other. According to the latest European 

 data, oranges stand first iu the amount of albuminoids (1.73 per cent), prunes second 

 (0.78 per cent), poaches (and probably apricots) third, banaujwj and grapes fourth, 

 while apples and pears stand nearly the lowest on the list (0.375 percent). Our 

 determinations of the same substances in California oranges as a whole (rind 

 included) show materially sujaller figures, averaging 1.20 per cent ; and as it is known 

 that the rind is very poor in these substances, we are forced to conclude that the 

 California fruit is less nourishing than that of Sicilian production. Miich lower per- 

 centages, however, are quoted for oranges from other sources. Here again the 

 ditVereuces observed may be largely due to the ago of the trees bearing the fruit, 

 which in California is usually the minimum. 



