ERICA MACK AYA'NA. 
MACKAY’S HEATH. 
Class. 
OCTANDRIA. 
Order. 
MONOGYNJA. 
Natural Order. 
ERICACEAE. 
Native of 
Height. 
Flowers in 1 Duration. 
Discovered 
Ireland. 
1 foot. 
June, Aug Perennial. 
in 1834. 
No. 780. 
Erica, see No. 217. Mackayana is given as a 
specific name after its discoverer, J. T. Mackay, 
Curator of the College garden, Dublin, a zealous 
and talented cultivator and botanist. 
This is a dwarf and very pretty Heath, lately 
discovered in Ireland, and deserving cultivation, as 
well for its beauty as for a memento of the opposing 
opinions of botanists. Our acquaintance with it 
commenced in the botanical section of the British 
Association, at Liverpool, where its claim to be dis- 
tinguished as a species was warmly argued. Hooker, 
Bentham, and Babington, now support its specific 
distinction; whilst Dr. Graham as strongly denies 
its legitimate claim to such honour. 
He considers it but one of the many forms of 
tetralix, and informs us that he has traced it, on its 
native heath, in many grades, from one extreme form 
to the other, and that he has also here, and in other 
places, gathered an umbellate form, far less like the 
ordinary shape of tetralix than that which the most 
extreme shape of Mackayana assumes. 
It has long been observed that the geological 
strata of a country influence its vegetable produc- 
