86 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 



that they are local developments, which by insular isolation have be- 

 come fixed entities, and are really the result of natural selection. 

 Whatever the origin of these plants may be, they are now absolutely 

 definite and consistent." 1 



[E. MOLLE Torr., of Macoun' s list is based on one of the plants cit- 

 ed above as E. molle, var. sabuloneiwe.] 



Oenothera cruciata Nutt. Occasional on the slopes of the dry 

 dunes. J. Macoun (C. no. 21,193 in part); H. St. John, no. 1,283 

 (H). 



Fl. July and August. Fr. August and September. 



[O. OAKESIANA Robbins. The material so reported by J. 

 Macoun, (C. no. 21,193) is in part 0. cruciata, in part 0. muricata} 



O. muricata L. Common on the slopes of the dry dunes. Col- 

 lected by J. Macoun (C. nos. 78,527, and 21,193 in part); H. St. 

 John, nos. 1,284 and 1,285 (H). 



FL, Fr August. 



HALORAGIDACEAE. 



Myriophyllum tenellum Bigel. Very abundant and forming 

 solid bands submersed or emersed at the borders of the fresh-watei 

 ponds. Dr. A. H. MacKay in Trans. N. S. Inst. Sci. x. 320 (1900) 

 mentions specimens found by J. Macoun. Listed by J. Macoun, 

 and H. T. Giissow. H. St. John, nos. 1,287, and 1,288 (H). 



Fl. July and August. Fr. September. 



Hippuris vulgaris L. In the swampy margins of a few of the 

 larger and more permanent fresh-water ponds. Listed by J. Ma- 

 coun; and H. T. Giissow. H. St. John, no. 1,289 (H). 



Fl., Fr. August. 



UMBELLIFERAE. 



Ligusticum scothicum L. One single clump observed near the 

 brackish margin of Wallace Lake. H. St. John, no. 1,290 (H). 



FL, Fr. August. 



Coelopleurum lucidum (L.) Fernald. (C. actaeifolium (Michx.) 

 C. & R.) Infrequent on the slopes of the turf-covered dunes. Listed 

 by J. Macoun; and H. T. Giissow. H. St. John, nos. 1,291, 1,292, 

 and 1,293 (H). 



FL, Fr. September. 



1 Fernald, I. c. 30-31. 



