254 BULLETIN DE L'HERBIER BOISSIER. (6) 



remarks (leaves) « upper opposite, somelimes floating », I hâve never 

 seen spécimens of true lucens with floating leaves it is essentially a deep 

 water form; but as I hâve seen P. Zizii Roth from India it is probable 

 that this was the Indian plant with floating leaves. This seems to me a- 

 line of demarkation difficult to argue away, true lucens will not sur- 

 vive the drying up of the water it grows in for any length of time,. 

 Zizii will not only survive but grow. 



18. P. Gaudichaudii Cham. Linn. 2, 199 (1827). 



I feel almost sure that the poor spécimen in the herberium is refe- 

 rable to this species. Chamisso's material was poor ([ bave not seen it) 

 but his description answers very well. Herr Maximowicz ventured to give 

 it a name « P. tretocarpus » and dislributed it as such in his Japanese- 

 plants. But I poinled out to him that it already possessed three certain 

 naines; ie P. maliana Miq., P. mucronatus Presl, and P. Wrightii Mo- 

 rong. I may say hère that in the herberium, I hâve written up fully the- 

 synonomy of the spécimens, and it does not seem needfull to give long 

 lists of names hère. 



20. P. prselongus Wulfen in Roemer Archiv 3 r 331 (1805). 



A spécimen from N. America under this name may be an hybrid with 

 perfoliatus, it resembles much the P. perfoliatus L. var. Richardsonit 

 mihi ; but is scarcely that. and is certainly not typical prselongus. 



21. P. perfoliatus L. var. Richardsonii Art. Benn. in J. of Bo- 

 tany 25, 1889. This remarkable from of perfoliatus has leaves sometimes 

 4 l /t inches long, contrary to the ordinary resuit of increased vegetative- 

 powers, the fruit is larger than is the type, and is so abundantly pro- 

 duced that it cannot be an hybrid. In the Great Lakes in N. America it 

 commences to appear, and increases as one goes west, being in many 

 parts the only form, I hâve seen no spécimens of such forms as the var 

 macrophyllus Blytt from the eastern parts either of Canada, or the 

 United States. 



22. P. mysticus Morong Coult. Bot. Gaz, 5, 50 (1880). 



Known from two stations only in N. America. It is difficult to place this 

 under any olher species, its nearest ally seems P. pet^foliatus. 



23. P. crispus L. Sp. pi. éd. 1, 183 (1753). 



A spécimen from « Deleware » N. America. Prof. Tucherman mentions 

 that he has seen in a European herberium such spécimens. D 1 ' Morong 

 considers this introduced to N. America, as none of the old authors name- 

 il, but he has overlooked Pursh's account. In his Fl. Am. Sept. 120, 1814 

 he gives it « Canada to Virginia » and he marks it « v. v. » as having seen 



