THE AZORES 



427 



describes a new species from an altitude of 4000 feet in the mountains 

 of San Domingo in the West Indies. 



The mode of dispersal of the genus Arceuthobium is illustrated in 

 the cases of A. oxycedri and A. occidental as described bv T. Johnson 

 and G. J. Peirce in the Annals of Botany (Vols. II. 1888, XIX. 1905). 

 The seeds are discharged " explosively,' 5 and are about a millimetre 

 in size. Their flight may cover a distance of fifteen to twenty feet, 

 and on account of their viscid exterior they adhere firmly to sub- 

 stances, the attachment holding for many months or even for a 

 year. It is thus likely that birds actively disseminate the species, 

 carrying the seeds firmly adhering to their plumage. In this respect 

 Arceuthobium resembles Luzula, which is mentioned in this connection 

 in an earlier page of this chapter, and it is noteworthy that the two 

 genera have a similar distribution. 



Cakile edentula, Big. — See p. 384. 



C allium vulgaris, S. — Begins to flower at the end of July. Grows 

 at all elevations on Pico from the coast to the top of the peak. 



Campanula vidalii, W. — This plant is peculiar to the Azores. It 

 was first gathered by Captain Vidal in 1842 from " an insulated 

 rock " off the coast of Flores. Watson subsequently made an un- 

 successful search for it on the main island (p. 188). Afterwards 

 (1844-48) Mr. Carew Hunt found it " very locally on the coasts of 

 San Miguel and Santa Maria," and it was from one of these islands 

 that it was introduced into English gardens (Ibid.). It is one of 

 the most beautiful plants of the Azores, is stout and shrub-like, 

 attains a height of two feet, and has milk-white flowers, one to one- 

 and-a-half inches long, the corolla being constricted in the middle. 

 Trelease, who visited the group in 1894 and 1896, speaks of it as then 

 occurring " on cliffs and detritus by the seashore and on outlying 

 rocks around the entire island of Flores " (p. 128). He alludes to 

 the impression in the islands that it occurs in cultivation only outside 

 Flores and was originally derived from that island. However, in 

 1909 Druce found it on the cliff-side at Capellas on the north-west 

 coast of San Miguel (Journal of Botany, 1911), and the present writer 

 came upon it there on the same cliff-side in 1913. As regards its 

 habitats in the group, it should be borne in mind that when it was 

 first collected by Captain Vidal amd Mr. Carew Hunt, 1842-48, the 

 islands of San Miguel and Santa Maria were as much entitled as that 

 of Flores to be considered the proper habitats of the species, since 

 in all three cases the indications went to show that it was a scarce 

 coast plant. Where observed by Mr. Druce and myself on the cliffs 

 of San Miguel it was growing in its natural station. Both Dr. 

 Carreiro and himself regarded it as truly indigenous in that locality. 

 It did not come under my notice on Pico, but it may grow on San 

 Jorge, and I am inclined to consider that it was originally widely 

 distributed over the Azores and is on the road to extermination. 

 It seeds profusely and germination takes place readily as the 

 seeds lie on the soil. Like Watson, I raised plants in my garden 

 from Azores seeds ; but on the coast of South Devon they are much 

 injured by the severer frosts when kept out of doors "during the 

 winter, but few surviving. 



