434 



THE COMPOSITE FAMILY. 



XIII. DIOTIS. DIOTIS. 



A single, very cottony species, distinguished generally from Achillea 

 by the florets, all tubular, with two projecting ears at the base, which 

 enclose the achene and remain upon it after the upper part falls off. 



1. Sea Diotis. Diotis maritima, Cass. (Fig. 516.) 

 (Santolina. Eng. Bot. t. 141.) 



Hootstock perennial and creeping ; the 

 stems branching at the base, hard and 

 almost woody, seldom a foot high, co- 

 vered, as well as the leaves and involu- 

 cres, with a dense, white, cottony wool. 

 Leaves alternate, oblong, entire or 

 slightly toothed, about half an inch long. 

 Flower-heads nearly globular, about 4 

 lines diameter, in dense terminal co- 

 rymbs. Florets yellow and small. Ee- 

 ceptacle convex, with scales between the 

 florets. Achenes without pappus or 

 border except the persistent base of the 

 floret. 



In maritime sands on the Mediter- 

 ranean and Atlantic. Extends on the 

 English coasts up to Anglesea on one 

 side and Suffolk on the other, found also 



Fig. 516. 



on the coast of Waterford in Ireland. Fl. end of summer or autumn. 



XIV. TANSY. TANACETUM. 



Herbs, with much divided, alternate leaves. Flower-heads hemi- 

 spherical, in terminal corymbs. Involucral bracts imbricated, scarious 

 at the edges. Receptacle without scales. Florets yellow, all tubular, 

 or the outer ones ligulate but not longer than the others. Achenes 

 angular, with a flat top, without any pappus. 



A small genus, from the Mediterranean and Caucasian regions, dif- 

 fering from Artemisia technically in the shape of the achene, but more 

 evidently in the larger, more yellow, corymbose, not paniculate, flower- 

 heads. 



