93 



On the Cerastium latifolium (Linn.) var. Edmondsionii (Lond. Cat.); 

 and on the Seeds of Cerastium latifolium and C. alpinum. By 

 Hewett C. Watson, Esq., F.L.S., &c. 



Mr. EdmondstOn has lately favoured me with two specimens of the 

 Shetland plant which was described by that botanist as " a new Bri- 

 tish Cerastium," (Phytol. i. 497) ; and I have also seen others, which 

 were sent to the Botanical Society. These specimens entirely confirm 

 me in the opinions which were expressed in the same volume of the 

 ' Phytologist,' in dissent from those entertained by Mr. Edmondston, 

 namely, that the Shetland plant is an identical species with that 

 of the Highland mountains, (Id. 586) ; and also that the Highland 

 species is truly the C. latifolium of the Linnean herbarium, (Id, 717); 

 anything written by Mr. Bentham or Mr. Babingtoij notwithstanding. 

 Mr. Edmondston's specimens are distinguishable from my other wild 

 specimens, by their shorter capsules and usually (not constantly) 

 broader leaves ; which are the only characters to distinguish them, 

 even as a mere variety, from the species of the Highland mountains. 

 These slight differences may have some connexion with the low ele- 

 vation at which the Cerastium grows in Shetland, compared with its 

 position on the mountains of Scotland. Some of my garden speci- 

 mens, dried the second year after the plants had been removed from 

 the Grampians into the county of Surrey, scarcely differ from those of 

 Shetland in length of capsule or breadth of leaves. The seeds of Mr. 

 Edmondston's specimens con'espond with those of C. latifolium, as 

 described in the next paragraph. 



While writing about the Shetland Cerastium, in the former volume 

 of the ' Phytologist' (Id. 718), I mentioned incidentally that the seeds 

 of these two species differed considerably; those of C. latifolium be- 

 ing smaller, darker and muricate; those of C. alpinum larger, paler, 

 and simply rugose. On afterwards alluding to these two species, in 

 the 'London Journal of Botany' (Feb. 1844), I expressed a suspicion 

 that an accidental crossing of their names had occurred on the papers 

 in which the seeds were folded. This suspicion is confirmed by other 

 seeds, collected in my garden last summer ; those of C. alpinum (not 

 latifolium) being smaller and muricate, as well as darker in their co- 

 lour. But I am not quite prepared to say that these differences can- 

 not depend on the state of ripeness ; the seeds of C. latifolium being 

 less thoroughly ripened, and their skin being loose. Would this loose 

 skin have contracted in such manner as to produce the elevated points 



