66 CRUCIFERAE 



France, consider our plant to be a variety of L. heterophyllum and name it 

 canescens. This is the name which I have here adopted (unless indeed 

 L. heterophyllum, var. campestre, F. Schultz, Fl. Grail, et Germ, Exs. cent, iii 

 et iv, Intr. 30 (1840), may claim priority), because L. hirtuvi, Sm. Comp. Brit, 

 ed. 3, 98 (1818), the name used in the last edition of the Lond. Cat, is defined 

 as having ' siliciilis hirtis,' which is opposed to the description of our plant, 

 because L. Smithii, Hook., Brit. Flora of 1835, is more recent than L. hete- 

 rophyllum, Bentham, 1. c. of 1826, and because I do not consider the latter 

 plant specifically distinct from the var. canescens, as defined by Grenier and 

 Godron. 



If it be considered, on account of the reference by Smith to the E. B. t. 1803 

 and in opposition to his own diagnosis, that our plant ought to be called 

 L. hirtum, Sm., then a new name will have to be given to the Thlaspi Jiii'tum 

 of Linnaeus, and that name might be Lepidium Candolleanum. If the 

 three plants in question be considered to belong to one species, the type 

 should be L. hirtum (Linn.) with var. heterophyllum (Benth.) and var. Smithii 

 (Hook.). 



* Ii. Draba, Linn. Sp. PI. 645 (1753^. 



Cochlearia Braba, Linn. Sp. PI. ed. 2, 904 ^1762). Draba, Clusius. 



Syme, E. B. i. 218, t. 158, Nyman, 64. FL Oxf. 37. 

 Denizen. Waste places, railway banks, &c. Local. P. May-July. 

 First record. L. Braba, Maidenhead. The author in Fl. Oxf. 1886. 

 2. Ock. Waste ground, Grandpont (now lost). Blewbuiy. Very 

 abundant at Didcot. On a rubbish heap between Wantage and 

 Letcombe Castle. Near Uffington by the railway. 



4. Kennet. Abundant by the railway between Shaw and Lambourn. 



Newbury. 



5. Loddon. Near Windsor, Bolton King. Maidenhead by the rail- 



way, Fl. Orf. and Bep. of Bot. Exch. Club for 1888. Old Windsor. 

 L. Draba occurs in Oxfordshire, Bucks, Surrey, and Hampshire. 



THLASPI, Linn. Gen. n. 719 .Tournefort, Inst. t. loi). 



T. arvense, Linn. Sp. PI. p. 641 (i753\ Penny Cress, Mithridate Mustard. 

 T. majus, Tabernaemont (1590^. T. Dioscoridis, Gerard, 204. 



Top. Bot. 30. Syme, E. B. i. 202, t. 144. Nyman, 61. Fl. Oxf. 35. 

 Colonist. Agrestal. Cultivated and waste ground. Not uncommon. 



A. April- Octobei'. 

 First record. TJdaspi, one kind growes on Botley Hills, MS. in Lyte's 



Herbal, 1660. Thlaspi arvense, Treacle Mustard, Dr. Noehden, 



Mavor's Agr. Berks, 1809. 



1. Isis. Pusey. Near Cumnor and Dean Court, Boswell. Wytham. 



Buckland. Appleton. 



2. Ock. Marcham, Walker. Harwell, Lomax. Between Abingdon 



and Wootton, Boswell. South Hinksey, Sister Jane Frances. 

 Iffley Lock, Armstrong. Wantage. Frilford. Steventon. Cot- 

 hill. Didcot. Sandfoi-d. Hagborne. Grove. Charney Basset. 

 Shippon. Near Wittenham. 



