Mr Mackay's Flora Hibernica. 265 



within fifty miles of it." This is a highly curious fact ; but sup- 

 posing the plants to be varieties, it only proves their characters to 

 be singularly constant. If it is an ascertained fact that they are 

 really varieties, they ought to be acknowledged as such, and a scien- 

 tific truth recognized. It is very remarkable that Primula fai inosa 

 has not been found in Ireland.* 



The second part of the volume is from the pen of Dr Taylor, the 

 able coadjutor of Professor Hooker in the well-known Muscologia 

 Britannica. The acute observer is manifest in every page, but es- 

 pecially in the descriptions of the Hepaticce, which evidently exhi- 

 bit the result of a long series of observations upon the living plants. 

 A new genus {Hygrophila) is established to receive the Marchan- 

 tia irrigua of Wilson t (in Brit. Fl.) and we have two new species of 

 J unger mannia ; one hitherto confounded with J. epiphylla ; the 

 other parasitic upon Hypnum loreum, and so minute as to be only 

 visible under the microscope. Among the Musci we have a recent 

 acquisition (Gynostomum tortile, Schw.) a near species of Glyphomi- 

 trion, and a new species of Bridel's genus Zygotrichia. Ireland 

 seems to be exceedingly rich in lichens. Besides a host of species 

 already known as inhabiting the British islands, Dr Taylor has de- 

 scribed forty-three new species belonging to various genera, eleven 



* There is one other point well worthy of attention, — and yet but slightly 

 noticed in this work, — we mean the bog-timber of Ireland, more particularly the 

 pine tribe. Mr Mackay appears to have satisfied himself that not more than 

 one species of pine is found in the bogs, and that that is identical with the 

 Pinus sylvestris, for he says under that head, (p. 259) " this tree appears to 

 have been abundant in Ireland, as trunks of very large dimensions are often found 

 in the bogs," and expresses no doubt of their identity with the Scotch fir. Any 

 person reading this observation would suppose that the point was settled, yet, 

 indeed, there still remains great doubts on the subject, for apparently at least 

 two different kinds of deal exist in the bogs. One has a stem spirally twisted 

 in a very marked manner, is very inflammable, gives out a fine perfume when 

 burned, and is used in the place of candles and torches by the peasantry in 

 many parts of the island. One of them also, we believe the latter, has the root 

 far larger in proportion to the timber, than it is found to be in the Scotch fir. 

 It is more than a speculative point to determine the species, for since a fir once 

 grew to a very large size in the wetter of the Irish bogs, it might do so again 

 could we succeed in obtaining the same species of tree ; and there is no way to 

 come to the desired information, excepting by a careful and microscopical exami- 

 nation of the structure of every kind of bog-timber. 



f Old. Hepatic.e. Genus Hygrophila. — Male receptacle pedunculated, hir- 

 sute, with short scattered hairs. Female receptacle pedunculated, hirsute, with 

 short scattered hairs. Calyx none. Loculi univalved, carnose, opening at the 

 top with a vertical short fissure. ( Frond without pores. ) 



