252 Carruthers — On Fossil Araucarian Cones. 



regards the cone, by having the scales without wings ; and the 

 other, Eutassa (Eutacta, Link), for the Polynesian species distin- 

 guished by the possession of wings to the scale. Although these and 

 the other characters obtained from the number of the anthers and 

 cotyledons, the form of the leaves, and the germination, are of im- 

 portance, they have not been considered by recent systematists of 

 generic value, but sufficient only for the division of the genus into 

 two natural sections. Another peculiarity is possessed by the 

 majority of the Polynesian species, which is important in connection 

 with our fossils. The Brazilian species never exhibit externally any 

 division of the scale into an upper and under portion. The small 

 upper scale, so evident in A. BidwilU (Plate XI., Fig. 4) and A. excelsa, 

 and in the two fossils, is so reduced in them that it is only discover- 

 able on the upper siuface of the scale after it has been withdrawn 

 from the cone.^ This small upper scale is larger in the fossil than in 

 any of the recent species. Three different views are entertained re- 

 garding the nature of this portion of the scale. Eichard' and End- 

 licher^ describe it as an appendage to the seed ; the late Sir Wm. J. 

 Hooker* supposes it to be the dilated "upper base" of the scale-leaf 

 folded down upon its upper surface ; and Dr. A. Dickson,^ holding 

 that the scale of the Araucarian cone corresponds to the membranous 

 bract which subtends the scale of the pine cone, supposes this to be 

 the representative of the true scale in the cone of Pinus. But 

 whether a seed appendage, the folded base of the leaf, or the repre- 

 sentative of the scale in the pine cone, the matter of importance to 

 us is that it is so largely developed in the Australian and fossil 

 species. The sjDecimen of A. sjohcerocarpa is so preserved that it is 

 difficult to say whether the scales were vdnged, but there seems to- 

 me to be indication of short wings. It is, however, evident that 

 the fossils belong to the Eutacta section of the genus, and among the 

 species the cones of A. excelsa aptproach most nearly to them in size 

 and form, and in the structure of the scales. 



The affinities of these cones to recent Australian species are 

 the more interesting, because Owen, Phillips, and Lyell have shown 

 that the animals belonging to the same epoch have their nearest 

 allies in that continent. 



EXPLANATION OP PLATE XI. 

 Fig. 1. — Cone of Araucaria sphcerocarpa, two-thirds the natural size. 



(The original is preserved in the British Museum, and is from the- 

 Inferior Oolite, Bruton, Somersetshire.) 

 „ 2. — A scale of A. BidwilU, somewhat reduced, showing the upper small scale. 

 „ 3. — Scale from the apex of the fossil cone. 



„ 4. — Scale from the corresponding portion of the cone of A. BidwilU. 

 ,, 5. — A portion of the fossil cone, natural size, showing the single interior seed 



cavity. 

 „ 6. — A section of the scale of A. BidwilU. 



^ This character is wanting in A. CooJcii, E. Br. {A. coltimnaris, Hook.), from New 

 Caledonia. The scale of this species has, perhaps, the most largely developed wings, 

 but the small upper scale is even more reduced than in the American species. 



2 Eichard. Memoires stir les Coniferes, p. 87. 



2 Endlicher. Synopsis Coniferarum, p. 184. 



* London Journ. of Botany, vol. ii., p. 504. 



5 Edinburgh New Phil. Journ., 1861, p. 197. 



