Lathr&a Sqaamdria. 635 



tab. 378., in the text to which table it is not stated upon 

 what plant the dodder is represented : it may be that Cirsium 

 arvense is the species which Mr. Sowerby had intended. 



The dodder's " stalk twines contrary to the sun's 



apparent motion, or from right to left." (Lindley, in EncycL 

 of Plants, p. 105.) 



Lathrcea Squamaria. (I. 407., II. 70. 105. 294., V. 45 — 

 48. 505. 543.) — Having lately examined (in Northumberland) 

 several plants of the Lathrae v a Squamaria, I think that I have 

 ascertained the cause of one of the apparent "varieties of that 

 plant, or, rather, of the variations in the description of it by 

 different individuals. One of the first plants that I gathered 

 not being expanded, I placed it in water ; and, shortly after 

 it had opened, observed that the upper lip in the most 

 advanced blossoms was deeply cloven, as represented in the 

 figure given in English Botany, t. 50., but less so in the 

 younger flowers. The cause of this I did not then perceive : 

 but afterwards, having gathered several more plants expanded 

 in their place of growth, I found in them the upper lips 

 entire; although, in other respects, they were like those first 

 collected. Having put these, also, in water, I soon observed 

 that, although in the younger blossoms, before the style pro- 

 jected, the upper lip was decidedly entire, yet that, when the 

 style was exserted, the upper lip became cloven ; and that the 

 cleft deepened as the blossoms advanced. It then struck me that 

 this was caused by the tendency of the exserted style to rise, 

 and, by its upward pressure against the centre of the upper 

 lip, to cleave it; and I feel now convinced that this, in all the 

 cases I saw, was the cause of the cloven variety. The plants 

 otherwise (except in those points which I formerly noticed in 

 the last number of vol. iii. of Cheek's Journal of Natural and 

 Geographical Science) resembled the figure in English Botany. 

 If I remember right, the style is sometimes not exserted even 

 in the advanced flowers ; and, in those cases, the upper lip, I 

 suspect, will never be found cloven. 



To those botanists who have an opportunity of examining 

 this curious plant, I would suggest this as a subject worthy of 

 further enquiry; and also whether varieties in the clefts of 

 the corolla of some other flowers may not proceed from the 

 same cause ; or sometimes, perhaps, from the pressure of the 

 stamina against them. — W. C. Trevelyan. Athenceum, Lon- 

 don, May 4. 1835. 



Dr. Johnston has described Lathrae N a Squamaria in detail 

 in his pleasing Flora of Berwick upon Tweed, vol. ii. p. 284., 

 and inserted an engraving of it, t. 8. The Berwickshire ha- 

 bitats given of the species are, " Damp shaded woods, rare. 



Y Y 2 



