It is, however, from the records of Jurassic rocks that we obtain the most satisfactory information as to the great antiquity and the very wide geographical range of the ancestors of the recent genus. The plant-beds of the Yorkshire coast afford clear evidence of the occurrence of Araucarian trees in the woodlands of the Jurassic period. Petrified wood has been found at Whitby, associated with jet, showing the minute structural characteristics of the surviving species of Araucarieae, and it is not improbable that some at least of the Whitby jet has been formed from the wood of Araucarian plants. The carbonised remains of leafy shoots preserved in the Jurassic shales near Scarborough and on other parts of the Yorkshire coast include twigs hardly distinguishable from those of _Araucaria excelsa_, though the resemblance of external form alone, especially in the case of foliage shoots, does not amount to proof of generic identity. We have, however, the much more trustworthy evidence of cones and seed-bearing scales in which the characteristic features of living species are clearly shown. Seed-bearing scales almost identical with those of _Araucaria excelsa_ and other recent species have long been known from the Jurassic rocks of Yorkshire. From other parts of England where samples of Jurassic floras are preserved, as at Stonesfield in Oxfordshire, in Northamptonshire and elsewhere, equally striking examples of undoubted Araucarias have been found. Fig. 18 represents part of a large cone described in 1866 by Mr Carruthers from Jurassic rocks at Bruton in Somersetshire: this specimen, now in the British Museum, consists of one side of a spherical cone about 5 inches long and 5 inches broad; in size, as in the form of the seed-scales, it shows a striking likeness to the cones of the Australian species _Araucaria Bidwillii_, the Bunya Bunya of Queensland. Other equally convincing examples of Jurassic Araucarian cones and seeds may be seen in the museums of York and Northampton. On the north-east coast of Sutherland there is a narrow strip of Jurassic beds forming a low platform between the granitic and Old Red Sandstone hills and the sea. From these rocks Hugh Miller described several fossil plants in his _Testimony of the Rocks_, and an examination of a large collection obtained from this district by the late Dr Marcus Gunn shows that Miller was justified in speaking of Araucaria as a member of this northern flora. [Illustration: Fig. 18. _Araucarites sphaerocarpus_ Carr. From Jurassic rocks at Bruton, Somersetshire. (British Museum, 2/3 nat. size.)]