i?ie Cascarilla Bark. 369 



Jacquin, being perfectly convinced of the identity of the latter 

 with the Linnean Cascarilla^ and that the distinctions hitherto 

 relied on to keep them apart are of too trivial and variable a 

 nature to be entitled to the importance which has been assigned 

 them. The specimen in the Linnean Herbarium appears to 

 have been communicated by Philip Miller, and belongs to the 

 West India variety, with narrower leaves, and consequently is 

 what Jacquin meant by his Croton linearis. The glands at the 

 insertion of the leaf, I observe, vary from two to four, although, 

 in the specific character of linearis, they are stated to be uni- 

 formly two, and three in Croton Cascarilla. 



REMARKS ON MR NICOL's OBSERVATIONS ON THE STRUCTURE 

 OF RECENT AND FOSSIL CONIFER-E. By WiLLIAM MaC- 

 GJLLIFRAY, A. M. F. E. S. E. SfC. 



In a paper entitled " Observations on the Structure of Recent 

 and Fossil Coniferae," published in the last Number of the Phi- 

 losophical Journal, Mr Nicol, alluding to Mr Witham'^s ob- 

 servations on the structure of certain fossil plants, finds it 

 " necessary to guard the scientific world against placing too 

 much reliance on a work, containing so many inaccuracies." 

 As I had the pleasure of assisting Mr Witham in his investi- 

 gations, I believe it is in some measure necessary that I should 

 say a few words regarding Mr NicoPs statements. As to the 

 observations on the structure of the recent and fossil plants in 

 question, there is no occasion of adverting to them, as geological 

 botanists can easily satisfy themselves respecting the accuracy 

 of the descriptions and figures that have been presented by 

 Mr Nicol or Mr Witham. 



In the first place, it is asserted that " several distinct fossil 

 genera have been indicated by a person who has examined, and 

 that too very superficially, only three slices of three recent pines, 

 differing not essentially from one another."" Who is the person ? 

 For myself, I would say that the assertion is not true, were its 

 rashness not evident to all. Certain, however, it is, that the 

 structure of recent Coniferae has yet been but very superficially 

 examined ; nor is even Mr NicoPs explanation of it nearly so 



