138 
Camelina sattva (L.) Crantz. False Flax. 
Adventive in the settled districts and in cabin clearings. Collected 
with flowers and maturing fruit July 8, and with all its pods mature 
August 6. 
Government Hay Camp, Slave river, No. 2459; Pine Lake ranger sta- 
tion, No. 2460. 
Neslia paniculata (L.) Desv. Ball Mustard. 
Adventive in settled districts. Found with flow r ers and immature fruit 
during the first week in August. 
Government Hay Camp, Slave river, Nos. 2457, 2458. 
Brassica arvensis (L.) Kuntze. Sinapis arvensis L. Mustard. 
Adventive in the settled districts. Flowers and young pods collected 
August 4. The seeds are commonly used medicinally as a stimulant or 
emetic. Other species in this family have somewhat the same qualities or 
are used in poultices as counter-irritants. 
Government Hay Camp, Slave river, No. 2456. 
Sisymbrium salsuginosum Pall. 
Probably common in the Salt Plain prairies, the only region in which 
it has been found thus far. Collected with flowers and immature fruit 
June 15, and with flowers and mature fruit August 20. 
Near Heart (Raup) lake, No. 2483; near Mission Farm, No. 2482. 
Descuiainia Richardsonii (Sweet) 0. E. Schultz. 
Probably occasional in clearings and prairies. Found with flowers and 
immature fruit July 6. 
Pine Lake ranger station, No. 2463. 
Specimens collected in upland prairies on July 5 are too young for 
definite determination. 
Base of eastern slope of Caribou mountains, No. 2464. 
Erysimum cheiranthoides L. Cheirinia cheiranthoides (L.) Link. Worm-seed Mus- 
tard, Treacle Mustard. 
Common in open places on river banks and in cabin clearings through- 
out the area. In the prairies at the base of Caribou mountains it becomes 
very abundant, and its yellow flowers add much colour to the landscape. 
A predominating feature of the spring and early summer aspect of these 
prairies is the abundance of tall dead stalks of treacle mustard rising above 
the new green of the grasses. Early flowers appear about the middle of 
June, and immature fruit about the first week of July. Flowering is nearly 
over during the second and third weeks of August, and fruits are maturing 
in quantity. 
East shore of lake Mamawi, No. 2471 ; Murdock Creek district, No. 
2475; near Heart (Raup) lake, No. 2477; Fort Smith, No, 799; Pine Lake 
district, No. 2472; Round lake, about 18 miles south of Pine lake, No. 2476; 
Peace point, No. 2473; sink-hole 16 miles east of Moose lake, No. 2474; 
base of eastern slope of Caribou mountains, Nos. 2465, 2466, 2467, 2468, 
2469, and 2470; lower Slave river, No. 798. 
