1916] Flora of the Boston District,— XXIV 221 



R. palustris (L.) Bess. Not reported southward, but frequent 

 elsewhere. 



R. palustris (L.) Bess., var. hispida (Desv.) Rydb. Nearly as 

 •common as the type. 



R. sylvestris (L.) Waste places in moist soil, occasional. 



SISYMBRIUM. 



S. altissimum L. Roadsides and waste places, well distributed. 

 Introduced within 20 years. 



S. Loeselii L. Woolen-mill yard, Graniteville, Westford (C W. 

 Swan, Aug. 22, 18S3, specimen in herb. Yale University). 



S. officinale (L.) Scop. Dump, W. Cambridge (C. A. Weatherby, 

 July 10, 1909); near houses, Stoughton (S. F. Blake, July 4, 1911, 

 July 13, 1912). 



S. officinale (L.) Scop., var. leiocarpum DC. Waste places, 

 common throughout. 



S. pannonicum Jacq. Roadside, Tewksbury (C. W. Swan, July 

 10, 1883); woolen-mill yard, Graniteville, Westford (C. W. Swan, 

 Aug. 20, 1885). Specimens in herb. Yale University. A foreign 

 introduction. 



S. Sophia L. Waste ground, abundant in a small patch, wholly 

 gone the next year, Chelmsford (C. IF. Swan, June 15, 1884, speci- 

 men in herb. Yale University). 



S. Thalianum (L.) J. Gay. Waste ground off Parkway, Brookline 

 (/". F. Forbes, May 10, 1907). 



THLASPI. 



T. ARVENSE L. Waste and cultivated ground, frequent. 



[Sisymbrium incisum Engelm. and Tropidocarpum gracile 

 Hook, are reported from wool-waste at N. Chelmsford by Rev. W. P. 

 Alcott in Dame & Collins, Fl. Middlesex Co. 8, 10, 1888. As Mr. 

 Alcott's herbarium is not available for examination these records 

 cannot be verified]. 



[Isatis tinctoria L. is reported by Dame & Collins from Newton, 

 on the basis of a specimen in herb. Boston Soc. Nat. History, col- 

 lected by C. J. Sprague. As the specimen cannot now be found the 

 record cannot be verified]. 



C. H. Knowltox I Committee on 

 Walter Deane \ Local Flora. 



