352 The Flora of Wiltshire. 



Bradford. " By the side of the Avon at Chippenham and Lacock," 

 Dr. Alexander Prior. 



5. North-east District, By the canal between Swindon and Crick- 

 lade. 



Perhaps not uncommon in the county. The leaves of this species 

 vary much, sometimes being found entire, pinnatifid or toothed ; 

 this may be owing to the depth of water or strength of the current. 

 On such plants as grow entirely out of the water, the leaves are 

 smaller, broader, and merely serrated. Two varieties of A. amphibia 

 (Koch.) are noticed by Grenier and Godron in their " Flore de 

 France," viz. Var. a. longisilgiuum, pods long, tapering at both ends, 

 twice as long as the styles. Var. b. rotundisilignum, pods globular, 

 as tang as the styles. The shortness of the pod in this and some 

 varieties of the Marsh Water Cress, has induced many botanists 

 to associate them with the horse radish in the present genus. 



Camelina saliva, (Crantz.) Gold of Pleasure. Alyssum Engl. Bot. 

 t. 1254. C. fcetida of " Babington's Manual" has occasionally been 

 found in cornfields in several parts of the county. Probably intro- 

 duced from Germany with corn and flax, where it is extensively 

 cultivated for the expressed oil of the seeds. 



Vella annua, (Linn.) Annual Cresset. Valencia Cress. Cress 

 Rocket. Found on the authority of Ray, by Mr. Lawson in 1690 on 

 Salisbury Plain, not far from Stonehenge. This is the only locality 

 in England where V. annua (Linn.) is said to have been found. I 

 have sought for it, as many botanists have done, in vain. This 

 curious little plant is a native of sandy and waste fields, and along 

 way and wall sides in Spain, Balearic Islands, Mauritania, Sicily, 

 Greece, and Syria. Flowering in June. It is represented in English 

 Botany t. 1442, and there is a well preserved specimen in the 

 Sherardian Herbarium. 



> 



Thlaspi, (Linn.) Penny Cress. 

 Linn. CI. xv. Ord. i. 



Name. From thlao, (Gr.) to compress or flatten, on account 

 probably of its compressed seed vessels. 



1. T. arvense, (Linn.) Corn Penny Cress, or Mithridatc Mustard. 

 Engl. Bot. t. 1659. Reich. Icones, ii. 5. 



