Vhs gbnus MAE ah. 35 



Reconsideration of the Genus Marah. 



It was the maturer opinion of the venerable Torrey that his 

 once contemplated, though not in his day actually published 

 genus Megarrhiza was better regarded as a peculiar section of 

 Echinocystis ; and this view soon afterwards met with the 

 approbation of that specialist M. Naudin. When, now twenty- 

 three years since (Pittonia, i. 1-3), I adopted that opinion, 

 promulgated as it had been by two botanists far superior in 

 age and experience, and myself transferred the Watsonian 

 megarrhizas back to Echi?tocystis , I was unaware that this 

 latter name itself had not the priority. Having discovered 

 that Micrampelis of Rafinesque is the earlier name, and an 

 entirely unobjectionable one, for the East American generic 

 type, it was natural I should transfer the Pacific species and 

 give them names under l\Iicrampelis ; and this was done 

 (Pittonia, ii. 127-129). 



The attempt, long persisted in, to hold the Pacific type as 

 congeneric with the Atlantic and original Micrampelis , does 

 not quite satisfy. As to foliage and as to flowers the two are 

 indeed much alike ; but in mode of growth, no less than as to 

 form and duration of their roots, they are quite different ; also 

 as to the dehiscence of their fruits there is wide disagreement. 

 Moreover, in the earlier of my two papers cited I find myself 

 somewhat reprehensible in having described the seeds of the 

 Pacific group as being "from nearly globose to much com- 

 pressed." A seed, in order that it shall be describable as 

 much compressed ought to be almost flat ; and that is hardly 

 true of the seeds of any of the Pacific species, although the 

 variation of them, between one species and another, is not 

 inconsiderable. But certain it is that no Mara has seeds 

 approaching those of Micrampelis by any notable departure 

 from the orbicular in outline. Even when somewhat com- 

 pressed, they have never anything like that elongated melon- 

 seed shape which helps to mark as distinct the Atlantic type. 

 Add to these considerations the facts that all Mara species are 

 perennial by enormous fleshy roots ; that their seeds of such 



