﻿100 Dixon: New and rare Australasian 



ments agree with those given by Brotherus. Moreover the cells 

 of M. Ugulifolium Broth, are there cited as in the former category 

 (2.5 n), while the original description gives them as 12-15 m- I 

 suppose therefore some error in the "Musci." The distinction in 

 the character of the areolation is however a very real and marked 

 one, and well described by Brotherus; but it depends less on the 

 size of the cells than on the character of the papillcC. The cells in 

 fact in the first named group though smaller are not greatly smal- 

 ler than in the latter. In these they are large, arranged in regular 

 longitudinal series, and pellucid; each crowned with or rather 

 rising into a large prominent conical papilla or tubercle, which may 

 be minutely bifurcate above, but inconspicuously. In the other 

 group the cells while a little smaller are of the same form and 

 arrangement, but this is masked by the papillae with which they 

 are covered, — lower, dense, numerous, and much branched, so as 

 greatly to obscure both the cells and their walls, rendering their 

 size and outline very ill-defined (cf. Plate 9, figs. 5, 6). 



This character once appreciated will easily separate M. 

 erosulum from M. prorepens, and will show into which category 

 doubtful plants passing under the name of M. erosulum must go. 

 That all the New Zealand species of this group with hairy calyptra 

 belong to one or other of these two species I am not prepared to say. 

 In any case the "ilf. microstomum" of the Flora of New Zealand 

 is, I think, generally agreed to belong here and not to the true 

 Oceanic species; I have practically no doubt that M. papilli- 

 folium C. Miill. is identical with M. erosulum. M. grossirete C. 

 Miill. and M. rigescens Broth. & Dixon have the capsules gymno- 

 stomous, and perhaps rather narrower, and these may be characters 

 of sufficient value — if stable — to allow them distinctive rank. 



Mitten named certain plants in his herbarium and at Kew M. 

 abbreviatum, from the short seta. In his original specimens it 

 varies from 2 to 3 cm. Within certain limits this is no doubt a 

 good character. But in the allied species M. prorepens it varies 

 very markedly; on the same stem setae of 2 cm. and even less occur 

 with others reaching 4 cm. And in specimens from Lord Howe 

 Island, McGillivray, which Mitten has named (on the strength of 

 this character) M. abbreviatum, but which indubitably belong rather 

 to M. prorepens, the seta is absurdly — perhaps pathologically^ 



