NATURAL SCIENCES OP PHILADELPHIA. 521 



half tuniified, so as to form, as it were, grooves between them, crossing the 

 ribs at au angle of about 60, (these are much more strongly marked when 

 the bark is removed) ; vascular scars three, composed of a central dot with a 

 curved linear impression on each side. 



Locality. Hazleton Mines. Cabinet of the Academy. Presented by Matthew 

 Baird, Esq. 



S. n o t a t a , nobis. 



Phytolithus notatus, Steinh., S. elliptica, Brong. S. atcenuata, Lesq. 



We see no character on which Prof. Lesquereux's species can be separated. 

 He says: "This species, viz. figs. 1 and 2, could perhaps be referred to 

 S. elliptica, Brgt. and viz. fig. 3, to S. Sillimanii, Brgt. But the form of the scars 

 in figs, one and two is broader and shorter than in the varieties of S. elliptica. 

 The author (Brongt.) says that ' S. elliptica has the scars only half as broad 

 as the ribs, whilst in our species they fill nearly the whole breadth.' ' After- 

 wards, when reconciling the three varieties together, he says, " But it must 

 be remarked with Artis (Anted. Phytol.) that the distance between the scars 

 of the leaves, as also the breadth of the ribs, is variable on the same tree. 

 The ribs enlarge towards the base of the tree and the scars become broader 

 and nearer together." Now is not this argument as applicable to the identity 

 of S. elliptica and S. attenuata, as to that of the three varieties of the latter. 

 which certainly differ as much, if not more, from one another, than from the 

 different forms of 5. elliptica ? The most important character separating the 

 two ? species, as given by the Professor, is the difference in the pro- 

 portion of the width of scars to that of ribs. The breadth of the scars in his 

 first variety is certainly very great, but in au English specimen (which we 

 doubt not was Steinhauer's type) now in possession of the Academy, the 

 breadth of the scars bears a proportion to that of the ribs almost as great 

 as in Lesquereux's second fig. and much greater than in his third variety. 

 Some of the varieties of S- elliptica, Brongt., figured by Groldenberg, (Flor. 

 Saraepont. Fossil.) also scarcely differ in this respect from the second form 

 of S. attenuata, and have the breadth greater than in the third variety. The 

 Professor remarks : " The reason for admitting these three specimens as three 

 forms of the same species are ;******, and that they have the 

 same general form of scars, ribs, and furrows ; the same disposition of scars of 

 the vessels either upon their naked surface or the corticated narrow striated 

 portion." These are the very reasons which have influenced us in uniting 

 the different forms; the specimens in the foreign collection of the Academy 

 possessing these characters in common with Lesquereux's plates. We have 

 elsewhere shown that S. e'liptica, of Brongt., is synonymous with Phytol. 

 parmatus, of Steiuhauer, and that S. notata, Br., (if it is a good species) is not, 

 and therefore propose to call the latter S. Brongniartii. 



Sub-genus Syringodendkon, St. 

 S. bistriata, nobis. 



Stem ecostate ; bark thin, striate ; stria very numerous, flexuous, occurring 

 in two forms, the one deep and strongly marked, the other small and straighter ; 

 scars sub-rotund, disposed in pairs about eight lines apart, very small. 



When decorticated, the scars are very elongate, often pyriform, and the 

 stria? very numerous, small and less flexuous. 



Cabinet of the Academy. Locality unknown . 



Note. I take this opportunity of correcting the very numerous typo- 

 graphical errors in my recent catalogue. The printer faiied to send to me a 

 revise, and errors noted in the first proof were not corrected, and consequently 

 misprints abound. The following are the most important : 



Page 436, substitute Catalogue of Foreign Carboniferous, &c, for "Cata- 

 logue of Carboniferous," &c. ; line 22, their for " these" ; 1. 33, macrodon for 



I860.] 



