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A NEW SPECIES OF SPLACHNOBRYUM, 

 WITH NOTES ON THE PERISTOME. 



By H. N. Dixon, M.A., F.L.S. 



(Plate 484 a.) 



In the winter of 1904 Mr. G. Webster sent me for identification 

 a small moss gathered in October of that year on brickwork in a 

 stove or warm forcing-house containing orchids at Baldersby Park, 

 Yorkshire, which upon examination was evidently a Splachnobryum. 

 This genus, as is well known, consists entirely of tropical and sub- 

 tropical species, only occurring in temperate regions as an alien, 

 introduced with stove plants, as was the case with the moss gathered 

 in the Botanic Gardens, Glasnevin, Dublin, and referred by Braith- 

 waite (Journ. Bot. 1872) to S. Wrightii C. M., a West Indian 

 species; and more recently with a plant gathered in stoves at 

 Cherbourg by Corbiere, and described as a new species, S. Corbieri 

 Ken. & Card. (Bull. Soc. Roy. Bot. Belgique, xli. p. 811, 1902-3). 



The genus Splachnobryum, founded by Carl Miiller in 1869, is a 

 well-defined one; twenty species were given in the Genera Muse. 

 Frond, of that author in 1901, a number already increased by three 

 in 1902, when the genus was described by Brotherus (Engler & 

 Prantl, Pflanzenfamilien, Musci, p. 420). Since that time several 

 fresh species have been described, including S. Geheebii Fleisch., 

 S. rostratum Broth. & Paris, and S. Corbieri referred to above. 

 Comparison with the descriptions and specimens in my possession, 

 and with the collections at Kew and the British Museum (the latter 

 including the types of most of Bescherelle's species) failed to 

 identify the Baldersby plant, and I therefore sent it to Dr. Bro- 

 therus, who kindly gave me his opinion that it was an undescribed 

 species. I quote from his letter : — "Diese, wie es mir scheint, neue 

 Art ist mit S. Wrightii und 5. Baileyi verwandt, weicht aber von 

 den erwahnten Arten durch weicheren, dunkelgriiuen Blattern, 

 kiirzere und diinnere Seta, durch kleinere, kiirzere Kapsel und lan- 

 geren Deckel ab. . . . Ich schlage Ihnen den Namen S. delicatulum 

 vor und hoflfe dass Sie gelegentlich diese neue Art beschreiben 

 wollen." 



Later on in the winter Mr. Webster paid another visit to the 

 spot, but found the plant had almost or quite disappeared. It, 

 however, reappeared the following autumn, and, curiously enough, 

 in October of that year he found the same plant in an orchid-house 

 at Harrogate. In this case the plants were mostly male, and no 

 fruit was present. The orchids in this house were at the time 

 mostly South American species, but this can scarcely be taken as 

 any guide to the origin of the moss, which is doubtless an annual 

 species, and may have occurred in the stoves from year to year for 

 some time past. 



The publication of the species has been somewhat delayed for 

 the following reason. When I came to examine the structure of 



Journal of Botany. — Vol. 45. [March, 1907.] H 



