2 
LORQUINIA 
seeds have a sweetish taste and, when roasted, are much prized by the 
Chinese as an article of food. 
The Ginkgo was formerly regarded as belonging to the order 
Coniferae, but is now referred to the new order Ginkgoacese. It has 
some characteristics in common with the conifers, being gymnosperm- 
ous and the cell structure of the wood is very similar, but it dififers in 
having a large central pith. Its nearest kin is probably the Cordaitales, 
a family now extinct, but which was very common in the forests of the 
carboniferous age. The fossil wood of these plants is found in the 
Upper Coal Measures with the cell structure very perfectly preserved. 
The character of the foliage of the Ginkgo seems to indicate a 
relationship to the ferns and their allies. The leaves are fan-shaped 
and have a general resemblance to those of the maidenhair fern, while 
the venation is similar to that of certain ferns. The veins radiate from 
the petiole, forking as they approach the margin of the leaf. There 
are also a number of veins which spring from the lateral margins and 
extend into the leaf-lobe. The leaves are wedge-shaped with consid- 
erable variation. Many are two-lobed, some are cleft very deeply, 
others only slightly, while many show no trace of dissection. By their 
peculiarities they are readily recognized when found in the fossil state. 
The order Ginkgoacese is believed to have had a wide range of 
distribution during Mesozoic time, particularly the Triassic and Juras- 
sic periods when it seems to have reached its culmination, and when a 
very equable climate prevailed and when gymnospermous trees were 
dominant in the forests. There is strong evidence that the range in 
time extended into the Carboniferous age, the fossil leaves having 
been reported as numerous in the coal-beds of that period. 
The nut-like fruit of the Ginkgo very closely resembles the fossil 
nut Trigonocarpus which is often found in the coal-beds of the Car- 
boniferous. These fossil nuts are supposed to be the fruit of the Cor- 
daites, as they are found with the carbonized foliage and wood of that 
plant. These nuts are much larger than the Ginkgo seed but have the 
same general character. 
Though now confined to China in its natural habitat the Ginkgo 
seems to have survived in America as late as Tertiary time. F. H. 
Knowlton, in his Catalogue of Cretaceous and Tertiary Plants, has listed 
specimens representing several species from Mississippi, Montana, 
Wyoming, Vancouver Island, and several localities in British Colum- 
bia and Canada. They have been reported from John Day Basin in 
Oregon and they also occur in many parts of Europe and in Siberia. 
According to Scott, ''The sum of fossil evidence is of sufficient weight 
to prove the great antiquity of the gymnospermous family now repre- 
sented by the maidenhair tree, * * * which appears to be regard- 
ed as the one surviving member of an ancient stock derived from the 
same cycle of affinity as the Paleozoic Cordaitse once the dominant type 
of Gymnosperms."* 
*United States Geological Survey Bulletin 152. 
