American Species of Marchantia. 251 



entire or crenulate margin closely simulating that of M. Ber- 

 tcroana. Even here, however, the gradual decrease in the size of 

 the cells as the margin is approached is in contrast to the abrupt 

 decrease found in M. Bcrtcroana. 



In habit and in general appearance M. Berteroana resembles 

 M. polxmorpha very closely, and it is not surprising that the early 

 observers failed to distinguish it as a species. The thallus, to 

 be sure, is more robust, it tends to be thicker and more leathery 

 than in the northern species, and the rays of the female receptacle 

 tend to be shorter, but these differences are not always pro- 

 nounced. There are, however, several distinctive features, in 

 addition to the scale-appendages, which deserve to be emphasized. 

 In the first place M. Berteroana seems to lack marginal scales 

 altogether. Sometimes the laminar scales form a vague double 

 row, some of the scales being nearer the margin than the others, 

 but even under these conditions there is quite a little space 

 between the outermost scales and the margin. In most cases 

 the row of laminar scales is more definite and the region without 

 scales is consequently wider. In M. polymorpha the marginal 

 scales are apparently always present, although they do not always 

 attain the same degree of development. M. Berteroana is further 

 distinguished by its cruciate epidermal pores, and by its lack 

 of epidermal papillae on both thallus and female receptacle. The 

 lack of marginal scales, the crenulate scale appendages, and the 

 cruciate pores will serve also to distinguish M. Berteroana from 

 M. plicata, although there is no evidence as yet that their ranges 

 overlap. 



The writer has fortunately been able to examine an original 

 specimen of M. cephaloscypha. The species was based on gem- 

 miparous material with young female receptacles collected some- 

 where in New Zealand, neither the date nor the collector's name 

 being given. A few years later Stephani^^ referred to his species 

 a series of specimens from various parts of Australia and was 

 able to add the characters derived from mature female receptacles 

 and ripe capsules. In his Species Hepaticarum," in addition to 

 New Zealand and Australia, he cites Tasmania, Fuegia, Pata- 

 gonia and Chile as localities for the plant and notes that it is not 



'' Hedwigia 28 : 265. 1889. 



''Bull. Herb. Boissier 7:391- 1899. 



