CONTRIBUTIONS TO THE ANATOMY OF MESOZOIC 



CONIFERS 



NO. 2. CRETACEOUS LIGNITES FROM CLIFFWOOD, 



NEW JERSEY 1 



Ruth Holden 



(with plates xii-xv) 



Araucarioxylon 



One of the most interesting and, at the same time, most dis- 

 puted questions in the phylogeny of the Coniferales deals with the 

 relative antiquity of the abietineous and araucarian lines. The 

 general ligneous structure of the latter has led the majority of 

 botanists to its direct affiliation with the Cordaitales. In a recent 

 paper, Professor Jeffrey 2 has shown that this resemblance exists 



mature w< 

 traumatic 



different 



6 



become 



ma 



and 



approximated 



tered and opposite. Moreover, in the cone axis the pits are sepa- 

 rated by well marked cellulose bars of Sanio. All these feature - 

 are characteristic of the Abietineae. and diametrically opposed to 

 anything found in the Cordaitales. The locality of these digressions 



from 



On both 



the zoological and botanical sides, the law of recapitulation is 

 regarded as one of the fundamental conceptions of evolution, and 

 according to this law it is in the plant seedling that ancestral 

 features should be found. Further, case after case has been 

 recorded where these primitive conditions are retained in the 

 root and reproductive axis, and recalled in traumatic tissue. A 



1 Contributions from the Phanerogamic Laboratories of Harvard University, 



no. 63. 



EFFRE 



Araucarioxylon type. Proc. Amer. Acad. 48:531-571. pis. 7. 19 12. 

 Botanical Gazette, vol. 58] 



[168 



