320 EVANS. 



of M. nitida and which is here included among the synonyms of M. 

 hamata, was based on a series of five specimens, one from Lord Howe's 

 Island, collected by De Camera, and the others from various parts of 

 Australia. In the Mitten Herbarium none of the Australian speci- 

 mens listed by Stephani (in his original description) are represented, 

 but a specimen collected by De Camera on Lord Howe's Island is 

 included in the M. australis cover. This specimen is fragmentary and 

 hardly determinable, but its marginal hairs are borne singly. It dis- 

 agrees therefore with M. hamata but it disagrees equally well with 

 Stephani's description of M. australis, according to which the hairs 

 are normally borne in pairs. The other characters brought out are 

 the following: a dioicous inflorescence; a convex thallus with abruptly 

 recurved margins; ventral hairs restricted to the costa; cortical cells 

 of costa in two rows both dorsally and ventrally; alar cells averaging 

 about 45 jjl. These are all characters of M. hamata, as Lindberg's 

 description clearly shows, and no differential characters of importance 

 are indicated. Whether the specimen from Lord Howe's Island in the 

 Mitten Herbarium is identical with the one listed by Stephani could 

 only be determined by a comparison. If they should be identical it 

 would simply prove that his original M . australis was an aggregate. 



In its convex thallus and in the structure of its costa M. hamata 

 bears a certain resemblance to the smaller M. magellanica. In M. 

 hamata, however, the marginal hairs are normally borne in pairs, the 

 alar cells average about 50 /x in length and the costa is hairy below; 

 while in M. magellanica the marginal hairs are borne singly, the alar 

 cells average about 28 ijl in length and the costa is naked. 



It will be seen from the preceding pages that the following valid 

 species of Metzgeria, although reported from Chile by earlier writers, 

 are not here recognized as members of the Chilean flora; M. conjugata, 

 M. furcata, M. albinca, M. Liebmanniana, and M. pubesce?is. In the 

 case of the last three species the Chilean records have all been carefully 

 investigated, usually by means of the actual specimens upon which 

 they were based, and found to rest on incorrect determinations. The 

 same thing is true of most of the records for the first two species, but 

 one record for M. conjugata and three for M. furcata remain to be 

 further considered. 



The record for M. conjugata is the following: Chile, Hahn (see 19, 

 p. 951). The specimen in the Boissier Herbarium, upon which this 



