242
THE ESSEX NATURALIST.
Turkestan. The cultivation of T. durum and T. polonicum is
characteristic of Abyssinia and although T. turgidum is not
found there, its nearest ally, T. pyramidale or Egyptian Rivet,
is almost exclusively Abyssinian, though its cultivation extends
to Upper Egypt. None of these ' races' can be said with safety to
have been grown in Europe in prehistoric times ; none of the
cereals enumerated by Theophrastus or by Pliny can be definitely
identified with any of these races ; the only authentic evidence-
that one of them, T. durum, was grown in Egypt, comes from a
deposit dating so late as 100 b.c. We find no definite evidence
that T. durum or Macaroni Wheat, or that T. turgidum or Rivet
Wheat, were grown in Europe before the XVIth century ; we do
know that their existence was not recognised till the middle of
that century. In the case of T. polonicum there is definite
evidence that it was not grown in Europe till towards the close
of the XVIIth century. Prof. Vavilov, finding the "centre of
"diversity" of this group of "races" in North-eastern Africa,
especially Abyssinia, concludes that this region must be their
"centre of origin." Mr. Haldane considers that they may
"have originated within historic times, in the Mediterranean
"basin, probably from Emmer."
The cultivated "races" of Wheat with 21 pairs of chromo-
somes are more controversial botanically and more interesting
historically than the group of "races" with 14 pairs of chromo-
somes that may have been evolved from Emmer. For our pre-
sent purpose it is convenient to deal first with the one member
of this "series" which may, like the members of the group to
which Macaroni Wheat belongs, "have originated within his-
"toric times," and at the same time is the only member of its
"series" which shares with the most primitive Abyssinian and
Indian varieties of cultivated Emmer, the character of a fragile
rachis.
Of all the wheats with a fragile rachis, Triticum Spelta, the
Dinkel or Spelt Wheat, is the one now most extensively culti-
vated, especially in Germany and in Spain. There is no record
of its occurrence in Africa, China, India or Persia. No Spelt
has been found in ancient Egyptian deposits. Spelt has never
been met with in any European Neolithic settlement, and
there is only one quite doubtful specimen from a late Bronze
Age deposit in Switzerland. Scholars have identified the πυρός