NOTES ON THE HISTOLOGICAL STRUCTURE AND SPECIFin GRAVITY OF 
THE SEEDS OF PYRUS. 
BY L. H. PAMMEL AND LUELLA KOBE. 
A number of investigators have made a careful study of the seeds of the 
common quince (Pyrus vulgaris), largely because of its use in connection with 
medicine and the interest attached to the mucilaginous character of the epi- 
dermal cell walls of the outer seed coaU. Little attention, however, has been 
paid to the structure of the seeds of the common apple. Kratzman^ Vinton and 
Moeller^ HilP, and Harz® call attention to the structure of the testa. 
The cultivated apple is a very variable species, not only with reference to 
the general morphology of the seeds, fruit, flower and leaves, but the micro- 
scopical structure also shows considerable variation. This is not strange if one 
considers what the probable origin of the apple is. The so-called Pyrus malus 
is variously considered as having been derived from a wild form which exists 
in Europe and eastward as indicated by Prof. Beach®, who says: “The original 
home of the apple, P. malus, is not definitely known. After examining the evi- 
dence carefully A. DeCandolle came to the conclusion that it is most (?) in- 
digenous to the region south of Caucasus, from the Persian province Ghilan on 
the Caspian to Trebizond on the Black Sea, and that from prehistoric times it has 
existed in Europe, both wild and cultivated, over an area extending from the 
Caspian Sea to the Atlantic Ocean, except in the extreme north. He cites 
it as being found wild in the mountains of Northwest India, but not in Japan, 
Mongolia or Siberia.” 
Focke'^ says that the apple was known in both wild and cultivated forms in 
very early times, having been grown by the Swiss in their Lake villages, and 
that numerous species now known are the results of crossing and careful selec- 
tion. A primitive, shrub-like form, P. pumila, still grows in the Caucasian and 
southern Altai regions and a somewhat more tree-like form, P. dasyphylla, is 
found in the orient, the flowers of both these varieties being somewhat woolly 
when young. The P. prunifolia, a garden tree, according to some authors, is 
found on the Siberian-Chinese borders and has a somewhat hairy blossom, woolly 
pistil and long stalked fruit; this is the primitive form of the Astrachan or 
Russian apple. Many species of the apple come from accidental crossing, and 
by cultivation these forms have become permanent. The Romans recognized 
twenty-nine varieties of the cultivated apple, while at present we have hun- 
dreds. 
See Bibliography. 
2. Kratzmann: Die Lehre von Samen 41. 
3. The Microscopy of Vegetable foods with special reference to diagnosis of mixtures 323. 
4. Annals of Botany 20; 395. 
5. Landwfrthschaftliche Samenkunde. Berlin 1885. 
6. Beach, Booth and Taylor, “Apples of New York.” i. 
7. W. O. Focke in Engler and Prantl, Die naturlichen Pflanzenfamilien , Rosaceee lir 
Theil. 3 Abth., 22. . 
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