RANUNCULACEJE. 73 



be borne in mind that the cold season should not become too long 

 in each year as the altitude increases, for then the number of species 

 would undergo some diminution. Thus of one hundred and thirty 

 species' found in France, we have not more than half a hundred on 

 the hiirh table lands of the south-east.^ The mineral character of the 

 soil usually appears to make less difference to these plants than to 

 many others. We see in our country Clematis Vitalha growing on 

 limestone or sandstone soils ; so will PukatiUa, the Wood and other 

 Anemones, the Columbine, Ficaria, many of the Crowfoots, and the 

 Aconites. However A. Anfhora prefers a calcareous soil, as do 

 Banunculus Thora, liybridus, Villarsii^ arvemis,^ Deljohinhim AjaciSy 

 Thalictrum aquilegifoUum, Adonis vernalis, &c. ; Callianthemum grows 

 on primitive soils,^ and Myosiirus minimus, Caltha ^jcdustris, TroUius 

 europceus, Adaa spicata, &c., seem to agree best with siliceous volcanic 

 soils. Some genera and species have a very large area, especially 

 (as always) the aquatic plants — Batrachium^ Caltha, Ranunculus 

 repens, arvensis, &c. The genus Ranunculus is represented in almost 

 every country of the globe. Almost all the genera belong to both 

 Worlds, viz. — Clematis, Thalictrum, Anemone, Ranunculus, Mi/osurus, 

 Caltha, Isopyrum, Aquileyia, Belphinium, Actcea, Paojiia. Only three 

 small genera are limited to America : Xantliorhiza, Hydrastis, and 

 Crossosoma. TroUius, Niyella, and Callianthemum grow in the Old 

 World ; while Glaucidium and Anemonopsis have only been found in 

 Japan. As many as a thousand distinct species have been admitted -^ 

 but fortunately the tendency now is to keep down the number, 

 which appears to have been far too much multiplied, many forms 

 having been raised into distinct species by monographists.^ 



To man the RanunculacecB are sometimes useful, often dan^rerous. 

 The foliage of many species has that dark green tint by which the 

 peasant instinctively recognises a dangerous herb. Then they are 

 often acrid, caustic, and poisonous. The Aconites, Hellebores, and 

 Crowfoots have been in all times celebrated for these qualities. 



* The number of species admitted by Geeniee Thalictrum alpinium, Myosurus aristaius re- 

 & GoDROX, op. cit., i. 3-53. present what are termed the disjoined species. 



- Lecoq, I. cit. 7 De Candolle in 1824 only knew 541. 



3 H. MoHL, ex A. DC, op. cit., 436. ^ Several of the species admitted by de CjlN- 



■* Lecoq, op. cit., iv. 483. dolle have been split up. Many entirely new 



* H. MoHL, ex A. DC, op. cit., 432. species have been since discovered, especially in 

 fi Ranunculus aquatilis is said to extend over America, China, and the Antarctic Zone. Never- 



at least a third of the earth's surfsice; so does thelcss Bentham & Hookee now-a-days only 



Caltha palustris. In this order R. anualilis, admit about 510 species. 



