Mr. C. C. Babington on British Plants. 429 



chiefly, acquainted with alhed species as preserved in an herba- 

 rium may have in appreciating their real distinctness. In this 

 instance the technical characters to be found in books are scarcely 

 sufficient for the separation of the plants, even when specimens 

 of each are before the student ; for it is found that the diflferences 

 in the shape of the leaves, calyx, corolla, &c., and the distri- 

 bution of the pubescence, are not so constant as to allow of 

 certain dependence being placed upon them. It is to the habit 

 of the plants that we must tm*n for a satisfactory distinction, and 

 unfortunately that is seldom to be well seen in a dried specimen, 

 although most marked in the growing plant. In Thymus Ser- 

 pyllum there is a manifest difference between the flowering shoot 

 and that which is intended to extend the plant. Quite prostrate 

 and rooting shoots are produced each year, which grow from the 

 end of the shoots of the preceding year, and do not flower : also 

 there spring from the other axils of those old prostrate parts of 

 the plant short erect or ascending shoots, which form a linear 

 series, and of which each terminates in a capitate spike consist- 

 ing of a very few whorls, and which die back to their base after the 

 seed has fallen. The growing shoot is thus seen to be perennial 

 and ultimately becomes woody, but the flowering shoot is annual. 

 In very vigorous plants the growing shoot is sometimes seen to 

 branch in a pinnate manner, and the flowering shoot similarly to 

 produce short branches terminating in small capitate spikes, but 

 their character as essentially growing and perennial, and flowering 

 and annual shoots, is not altered by their luxuriance. This mode 

 of growth causes the plant (especially if kept clear from weeds, 

 as is the case in a garden) to present the appearance of a cushion 

 of flowers surrounded by a prostrate fringe of leafy shoots. 



In T. Chamcedrys there is no such manifest separation into 

 flowering and growing shoots, but they all are alike in their 

 origin and appearance. The terminal bud often produces the 

 strongest shoot, which itself ends in flowers, but has usually 

 barren branches from some of its axils. It thus differs most 

 materially from the T. Serpyllum, in which the terminal bud 

 always produces a flowerless shoot to form the foundation for the 

 flowering shoots of the succeeding year, and to terminate in a 

 similar leaf-bud to that from which it sprung. A tuft of T. Cha- 

 rruedrys therefore has none of the beautiful regularity possessed 

 by one of T. Serpyllum, but presents, from the centre to the cir- 

 cumference, a dense irregular mass of leafy shoots and flowers 

 intermixed. In the autumn or winter these leafy shoots fall 

 towards the ground, and such of them as become buried produce 

 a few roots, increase in a caespitose manner in the succeeding 

 year and throw up intermixed leafy and flowering shoots. The 



