and Kushabar. It does not seem to have been previously observed in Siberia, and is not 

 mentioned in any of the floras from there within my reach. Korshinsky also declares 

 in Tentamen Florae Rossiae Orientalis, St. Petersburg 1898, p. 48: „Per Rossiam euro- 

 paeam distributa; terminum orientalum (secus jugum Uralense) in ditione nostra attin- 

 gens; deest in Sibiria et • Turkestania." It probably belongs to the series of weeds 

 nowadays spreading over Siberia by the improved means of intercourse. 



Distribution: From the Orient and European Russia the species seemed to be 

 wandering westwards through Europe, where it is known from middle and northern 

 Europe up to southern Scandinavia, as well as eastwards through Siberia, where I have 

 found it as for east as the government of Yeniseisk. 



Thlaspi arvense L. Spec. PI. ed. II (1763) p. 901; Ledeb. Fl. Alt. Ill, p. 94; Turczan. 

 Cat. Baical. no. 149; Karel. et Kiril. Enum. PI. Fl. Alt. no. 81; Ledeb. Fl. Ross. I, p. 162 

 et 756; Turczan. Fl. Baical.-Dahur. (1842) p. 263, no. 141; Kegel, PI. Radd. (1861) p. 

 201, no. 225; KpM.i. <l\i. Ajlt. 1 (1901) p. 87; Bymrb, Cruciferae Bt 'I>.i. Cuoiip. ii ^lUbn. 

 BocT. I (1913) p. 110. 



The species varies considerably in the height and ramification of the stem, and in the 

 size, length and breadth of the leaves, the margin of which is sometimes entire, or more or 

 less distinctly serrulate. In point of the shape of the young fruits the specimens collected 

 really seemed to have to be referred to f. typicum Busch (Rhoead. in Fl. Cauc. Crit. 

 Ill, 4 (1908) p. 157), though other specimens have more orbicular fruits, and the sum- 

 mits more broadly incised, so as to make them look more like f. baicalense (DC.) C. 

 A Meyer, Verz. Cauc. (1831) p. 184. 



These two forms therefore seemed to pass into each other. According to Ledeu. 

 Fl. Alt. Ill, p. 94, the latter form is not invariable when cultivated, either. The species 

 is scattered as a weed over the traversed regions of southern Siberia, on the borders of 

 fields, etc., on the Abakan Steppe, between Minusinsk and Kushabar, as well as in the 

 Urjankai country, where found by me near Ust Sisti-kem and at list Uss. Taken with 

 flowers and young fruits in June and the first half of July. 



Distribution: Throughout Europe, south-western Asia, through the Thian-Shan, 

 Pamir, and the Himalayas to China, southern Siberia and northern Mongolia, North 

 Africa. Introduced into North America. 



Sisymbrium officinale (L.) Scop. Fl. Carniol. ed. II, 2 (1772) p. 26; Ledeb. Fl. 

 Ross. I, p. 176 et 759; Kptu. clxi. A.tt. I (li»01) p. 92; Byuii., Cruciferae n-h cj).!. CiiSiip. 

 II JI^ajihH. Bdct. I (1913) p. 138. 



As a weed near Ust Abakansk. Only young specimens bearing flower-buds at the 

 end of June. 



Distribution: Europe, except the extreme north, Asia Minor, Syria, south-western 

 Siberia to the government of Yeniseisk, the Amoor Province, North Africa. Introduced 

 into North America and Australia. 



256 



