160 QUATERNARY PERIOD. 



same cycle of forms, which has been assigned to them during 

 uncounted ages. 



3. The larch (Pinus Larix, Linn.). From Morschweil and 

 Utznach Prof. Heer has procured some cones which may pro- 

 bably belong to the larch. They are small and oval, and have 

 striated scales, not thickened at the apex and obtusely rounded 

 like those of larch- cones. But as they are strongly compressed, 

 their scales are injured, and no seeds are to be seen, they can- 

 not be certainly determined. 



4. Of the yew (Taosus baccata, Linn.) Prof. Heer found the 

 nucule at Diirnten (fig. 342) : it agrees perfectly in form and 

 configuration with that of the living yew, but is a little smaller. 

 It has a roundish umbilicus, a very finely wrinkled shell, and a 

 small projecting point at the apex. 



5. The birch (Betula alba, Linn.). The trunks of this tree, 

 of considerable thickness, with their white bark, are, next to the 

 pines, everywhere the most abundant woody plants in the lignites. 

 In the fresh state their layers may be peeled off from the bark, 

 as in the common Swiss bh'ch; and the same striate lenticels 

 are shown. On the slender rod-like branches the white bark is 

 wanting, and they are of a brown colour. The leaves, fruits, 

 and seeds have not yet been found, and the species consequently 

 cannot be determined with certainty; but the perfect resem- 

 blance of the wood and bark renders it very probable that they 

 belong to the common Swiss birch. 



6. The oak' (Quercus Robur, Linn.). As yet only an acorn 

 with its cup has been found at Morschweil ; it was forwarded 

 to Prof. Heer by Prof. Deicke. The tips of the bracts which 

 form the cup are in part preserved, and they agree with those 

 of the Swiss oak ; but the cup itself is rather larger, and some- 

 what contracted above. Whether the fruit was sessile or pedun- 

 culate cannot be decided ; so that Prof. Heer cannot ascertain 

 whether it belongs to Quercus pedunculata or Q. sessiflora ; and 

 these two forms have recently been again united under one 

 species. 



7. The sycamore (Acer Pseudoplatanus, Linn.). Of this tree 

 Prof. Heer has discovered a few remains of leaves, 3 inches long, 

 in the lignitiferous clays of Binzberg near Diirnten. In their 

 strong secondary marginal veins and delicate venules issuing 



