224 Scientific Intelligence. 



;ree-fern with leaves i 

 1 Acadian Geology, p. 143), 

 and recognizes one of his French species as i<~ 

 McLeayi of Lesquereux. In the order Lye. >p. >dia 

 Lepidodendrem a separate family, including the g 

 (l-un mil Upi'hml 'jos. Thel'atter is an old and natural genus oi 

 Sternberg, very 'much ignored in England, but which has been 

 recogniz* i inci ii- I by paleo-botanists in this country. Under 

 the name P.-« "d .•_,•/;','/,•;.. h<- includes some stems referred by 

 authors to >7 ; ,//' .,'/, . hut wl ich, on grounds connected with the 

 nature and arrangement of the lent' scar.-, he very properly asso- 

 ciates with the Lepidodendra. There can be no doubt that 

 many cases of this kind exist; though it may be doubted whether 

 the founding of a genus for them is the best mode of disposing 

 of sucli doubtful specimens. Knorria and Halonia are recognized 

 as imperfectly preserved or aberrant Lepidodendrece. 



Perhaps the most remark, hie part or' this memoir is the great 

 development which if gives to the group of ( ivmnosperms. which, 

 as represented in the Coal formation, ho divides into the orders 

 of the Shj'dijiruK; o. the ( '<-r<!oni>'e>' and the i'nbnn.nd^jid r>>< ■(-_"•' 

 with the uncertain group of -Vocy,'/' ■rttthh; As !.o the Sigiilaria 

 family, he merely ventures to divide the ureal genu-- ' ' >'!« 

 into provisional -ub-genera in the same manner in which this has 

 been done by others; but he recognizes Syringodendron as a 

 separate genus. He thinks this last must have had \ cry minute 

 leaves, and he refers to it, as its roots, certain Stigmarioid organs 

 which he term- .v /<///. ,,■<■ , <>x, and which dilf. r ii - >me paiticulars 

 from the true Stlgmaria root. ,,} tin- >;,////./,■;,.. As to the true 

 Shjilhirht, he holds with Brongniait, and with Newberry and 

 the writer in America, that they are Cymuosperuious. 

 more precisely, that the true shjdliri.l are of this ran! 

 some of the species confounded with these by their sit 

 external markings, may be allied to the L<i r '<h>Jrndr<i. He does 

 not seem to have met with any specimens that show ihe advanced 

 structures, approaching to those of the Cycads,* found in some 

 Nova Scotian specimens, but he considers the structure of the 

 stem exogenous, and the resemblances which it presents to L>-p>- 

 d,,d, ,, dron as mere!; ■ i on to a similar habitat, 



lie has not found th . e, but believes that 



he has discovered indications of seeds borne on the bases of 

 leaves, and he is also inclined to accept the circumstantial 

 evidence adduced bv Dr. Newberrv and' the writer, that the 

 Tn : /-„ t ow r u and similar fruits mav have belonged to some 

 sp. cic .,-; sh/dl.tfUt. 



The elevation of the genus Cordons, hitherto very imp rf. ctlv 

 known, to the rank of the type of an order is a feature in thi- 

 memoir. In some parts of America the leaves of these pi;i"' s 

 occur in excessive abundance, beds of shale being filled with them 



* Incorrectly said to resemble Conifers, which is 

 perhaps from the imperfect way ia which they have b 



