IV. EXPLANATIONS, ETC. 321 



soinewliat more in detail, we trace out the latitudinal limits of the 

 austral and general plants to these numbers: — 

 Ceasing in 50 — 51 latitude, 27 species. 



51—52 „ 52 „ 



O-^ — o»5 }) y*' J 9 



53—54 „ 65 „ 



64—55 „ 146 „ 



55 — 56 „ 88 „ 



56—57 „ 104 „ 



57—58 „ 99 plus 49 and 35. 



58—59 „ 14 „ 29 „ 17. 



Orkney 17 „ 70 „ — 



Shetland 44 „ 100 „ 120. 



Tracing the plants through the provinces in the order of their corre- 

 sponding nos., we find the austral and general species ceasing north- 

 ward, and the boreal and montane species ceasing southward, in the 

 following numbers : — 



And distributing the numbers for the province of the North Isles, among 

 the three groups, the 376 species successively reaching or ceasing in 

 them run thus : — 



Hebrides 25. Orkney 87. Shetland 264. 

 VOL. IV. 2 T 



