1^ . 



Il 



ill I 



[If 



H 



I 



'! 



ifir, 



TIIR OEOLOOrCAL HISTORY OF PLANTS. 



mind tliiit Micy an; usiinlly the niiirUs f)f cones; uiid the ^rcfut size of 

 the cones of Jjc/ndoph/oioM nccords with Ihisconeiiision. 



The species of Lppidophloios are numerous, and individuals arc 

 quite abundant in the eoid formation, esjicciiiiiy toward its u[>p«r 

 I>art. TlicHr llattened bari< is frefjuent in the coal-beds and their 

 roofs, airordiri}^ a thin hiycT of i)ure <!oul, wiiich sometimes shows the 

 peculiar laminated or scaly charact(!r of the bark when other charac- 

 ters are almost (entirely obliterated. The leaves also are nearly as 

 abundant as those of ,Sif/tfl(iri(i in tin; coal-shales. They can readily 

 be distin;^iiishe(l by tluiir stronj,', atij,'uliir mid-rib. 



The marUin;^s of Lcpi(lo])hl()ioH may e/isily be mistaken for those 

 of the ('Ittt/irnrid type* of SifjiUdria. Whisn th»! stciui only is seen, 

 tli(\y can be distin^juishcd by lh(! len^jth of tlut leaf-bases in Fjcpi- 

 doph/oios, tintl by tin; dominatit ceiitrul vascular scar ; also by the 

 one-nerv(!d and riblxid leaves. Wlu're the lar^o, round marks of the 

 cones are pnisent, these are an infiillil)le ^uide, never beiiif^ f)resent 

 in JSii/il/(iria. As 1 he cones f^rew on the u|»per sides of I he branches, 

 the impiession of the lower side often shows no cotuj-scars, or ordy 

 two lateral rows, whereas on the upi)er side of th«! same branch they 

 aj)pear s|»irally arranj^ed. I may dest;ribeus an exam|tle — 



fjcpidop/i/oioi AcddidHUK, Dawson. Leaf-bases broadly rhom- 

 bic, or in old st(!ms rej^ularly rhoml)i(!, prominent, as(!(!ndin^', termi- 

 nated by very broad rhombii; scars havinj^ a central point and two 

 lateral obscure points. Outt^r bark laminated or .scaly. Surface of 

 inner bark with sinj^le points or depressions. Leave?; Ions', linear, 

 with a strouf? keel on on(! si<l(s five inches or more in lenj^th. Cone- 

 S(!ars sparsely scattered on tliick branches, either in two rows or 

 spirally, both modes b(!ing sometimes seen on the same brancih. 

 Scalariform axis scarcely an inch in diameter in a stem live inches 

 thick. Fruit, an ovate strobile with numerous acutu scahis covering 

 small globular spfin^-cases. This spcci(;s is closely allied to Uloden- 

 drnn majuti and LcpidopldoioH faricmuH, and presents numerous 

 varieties of marking. Coal-fonnation, Nova Scotia. ,: 



Family Calamitk.k ; (hmiH Catamites, Suckow. 



The {)lants of this genus are unrpiestionably allied to the mod- 

 ern EquiHatacec, but excel these so much in variety of form and 

 structure, and are so (.'apricious in their states of preservation, and so 

 liable to be mistaken f(jr parts of plants generically different, that 

 they have given rise to much controversy. The following considera- 

 tions will enable us to arrive at some certainty. 



The genus Calamites was originally founded in the longitu- 



itii I 

 iti 1 



