216 BOTANICAL GAZETTE [September 



character. The proof of the abortion of the second cotyledon and the 

 discovery of the manner in which that abortion was brought about 

 naturally revive the question of the monocotyledonous nature of 

 certain dicotyledons. It is possible that in some cases this condition 

 may be caused by the same factor which produces it in the embryo 

 of Ceratozamia, but this is not so in all cases; the experimental 

 work now in progress upon these forms shows that other factors, are 

 involved. 



The lobing at the tip of the cotyledon is suggestive of a primitive 

 condition, which will be discussed in connection with Dioon spinu- 

 losum. 



It would be interesting to compare the cotyledonary node in all 

 cycads, in order to determine whether they are modifications of the 

 same type or whether there are different types; but it is a matter of 

 regret that all investigators have not considered it of sufficient impor- 

 tance. Matte has described it fully for Dioon edule and Cycas 

 siamensis. The latter is clearly a modification of the type which may 

 be represented by the former. The present paper shows that Cerato- 

 zamia conforms to this type, and it may be in place here to say that 

 Microcycas and the species of Zamia I am investigating are the 

 same. Worsdell's Cycas revoluta and Macrozamia spiralis are 

 doubtless similar. Encephalartos Barteri according to Matte's 

 description, Zamia muricata according to Karsten's, and Bowenia 

 spectabilis according to Pearson's seem to differ from this type, 

 in receiving only one bundle from the central cylinder; but there 

 are two facts which conspire to make us consider that the seedling 

 of Encephalartos described by Matte was an unusual one: the 

 presence of three cotyledons, and the union of the cotyledonary 

 strands with the central cylinder at different levels. 



That cycads, especially such fernlike ones as Stangeria and 

 Bowenia, should be found to have an occasional concentric bundle 

 is only to be expected from the nature of their fern origin. Wors- 

 dell's announcement, then, of such bundles in the base of the coty- 

 ledon of Stangeria was not a surprise, even though his drawings 

 were not convincing. But the emphatic statement of Pearson that 

 he could not be convinced of it in Worsdell's preparation of 

 Bowenia raises the doubt whether he would have recognized it in Stan- 



