ROOM I. 



CTCADEOUS PLANTS OF PORTLAND. 



carbon, but the venation is distinctly preserved. In the 

 Stonesfield Slate, and in the Portland and Wealden strata, 

 remains of this tribe are met with. The Museum con- 

 tains many beautiful specimens of the leaves and fruits or 

 cones of the ordinary species, which are arranged in the lower 

 part of the Case before us Case F of the plan, p. 10. 



Of these the most striking is a well-known fossil plant of 

 the Scarborough Oolite, whose leaves and fruits occur in pro- 

 fusion in some of the strata. This species has been described 

 under the names of Zamia gigas, and Z. Mantelli, and has 

 lately formed the subject of an interesting paper read before 

 the Yorkshire Philosophical Society, by Professor Williamson 

 of Manchester. Several specimens of the fossils locally termed 

 " collars," are in the case before us : these bodies Professor W. 

 has shown to be a zone formed by a scaly bud which origi- 

 nally enclosed the germ of these plants : in the progress of 

 development the fruit burst through the upper part of the 

 investing sheath, and, as it grew to maturity, rose above the 

 incurved elongated scales, till the latter literally formed a 

 zone or " collar" around the pedicle of the cone. 



LIGN. 18. LEAVES AND FRUIT OF ZAMIA LANCEOLATA, FROM SCARBOROUGH. 

 (nat. size.) 



Zamia lanceolata. Case .P. On a slab of sandstone there 

 is a beautiful example of the foliage of this plant, with a 

 detached cone imbedded immediately above one of the leaves. 



