I902. . Reviews, 193 



name it bore, and that the constituent species of each would be such 

 only as found their focus or centre of development within the appro- 

 priate province. A study of the map on p. 34. and of the lists of species 

 given further on, shows, however, that such a conception of the areas 

 and constituents of these t3'pes would be far more limited than the 

 author's conception. The areas as laid down in this map are, in fact, to 

 use an appropriate botanical term, imbricate, so deeply imbricate, in- 

 deed, that the amount of overlap in some cases is equivalent to the 

 addition of a second province. Thus the area of the Ultonian t3^pe, as 

 laid down on Mr. Praeger's map, includes, along with Ulster, almost the 

 whole of Ccnnaught ; that of the Mumoniau type includes, along with 

 Munster, almost the whole of Leinster ; that of Lagenia includes, along 

 with Leinster, the greater part of Ulster and a large slice of Munster ; 

 while the Connacian area includes, in addition to Connaught, the greater 

 part of Munster with north-west Ulster. 



A certain degree of overlapping of distributional areas is unavoidable 

 in any scheme of topographical plant groups, but the efifectof such wide 

 overlapping as is provided for in the proposed scheme of provincial areas 

 has two undesirable results — it renders the title of each plant-group in- 

 appropriate, and to a certain extent misleading, while it obscures the 

 special character of the group by the introduction of discordant elements. 

 These objections apply with less force to the Ultonian group than to any 

 of the others. The large proportion of its members, no less than 82 per 

 cent., occurring in Antrim, where the focus of the group is placed, shows 

 that it is on the whole truly Ultonian. The exclusion of a few species 

 doubtfully focussed in Ulster, such as Vaccitiuwi Vitis-Idcea and Potamogeton 

 filiformis^ would make this group even more natural. 



When we come to the Mumonian type, whose focus is placed in East 

 Cork,we find that the maximum percentage of the group found there sinks 

 as low as 60, suggesting that the group is largely constituted of elements 

 not truly southern. Examination shows this to be the case. The list 

 includes at least 12 species which do not find their focus anywhere in 

 Munster, and whose inclusion only serves to obscure the true character 

 of the group. The most prominent of these species are Viola hirta, 

 Leontodon hispidtis^ Chlora perfoliata, Atriplex portulacoides, Potamogeton Jlabel- 

 latiis, and Bromtis erectics. The list at the same time includes two species, 

 Campamda Trachelitim and Colchicumautzininale,yf\\'\ch are altogether absent 

 from Munster. The type might advantageously be reduced from 66 to 

 50 species. 



The Lagenian type shows the high percentage of 80 in its focus, the 

 County of Dublin. Yet several of its species, for instance, Lepidium 

 hirtuni, Scilla vertta, Lemna gibba, Carex dioica, and Hordeiim secalimwi do not 

 properly belong here, since they cannot be said to find their focus any- 

 where in Leinster ; two others, Elatine Hydropiper and Zannichellia poly- 

 carpa, do not occur at all in that province On the whole, however, this 

 group is a natural one. 



In the focus of the Connacian type, West Galwaj', the percentage of 

 the group falls to 60, or 37 out of a total of 63, suggesting, as in the case 



