CHILEAN SPECIES OF METZGERIA. 313 



bluish coloration after being dried; the thallus is rarely distinctly 

 convex; the gemmiparous branches, although specialized, develop 

 gemmae only from alar cells; and the gemmae themselves are plane 

 or only slightly convex. 



Stephani's M. angusta, to which he referred some of Dusen's speci- 

 mens of M. riolacca, was based on material from Brazil, Venezuela, 

 Trinidad, Mexico, Guatemala, Louisiana and Santo Domingo, as well 

 as from Chile and Patagonia. He speaks of Dusen's specimens as 

 exceedingly reduced, so that in all probability they are distinct from 

 the other specimens cited. According to the description of M. 

 angusta the wings are everywhere eight cells wide, the alar cells 

 measure 54 X 37 n, and the costa is setulose throughout on the ventral 

 surface. It will be seen that this description does not apply very well 

 to the specimens of M. violacea. The description of M. antarctica 

 applies much better, except that the wings are usually much narrower 

 than 0.7 mm., the measurement there given. It is unfortunate that 

 Stephani made no mention in his description of the gemmae and 

 gemmiparous branches, which certainly yield the most distinctive 

 characters of the species. 



10. Metzgeria magellanica Schiffn. & Gottsche. 



Metzgeria magellanica Schiffn. & Gottsche in Schiffner, Forschungsreise 

 "Gazelle" 4 4 : 43. pl.8,f.6. 1890. 



Specimen examined: Tuesday Bay, Straits of Magellan, 1876, 

 Naumann (S., Type); known with certainty only from the type 

 locality. 



The type material of this interesting species, kindly sent for examina- 

 tion by Professor Schiffner, shows that it is amply distinct from M. 

 niiida, under which Stephani included it as a synonym (see p. 272). 

 The plants are a dull whitish green and grew in loose mats in admix- 

 ture with other bryophytes, including a trace of M. decipicns. The 

 thallus is normally so strongly convex that it approaches a terete 

 condition, the revolute wings almost meeting below, as shown in the 

 published figure. Of course, as would be expected, the convexity is 

 sometimes less pronounced than this, and the thallus may even approx- 

 imate a plane condition. The width when explanate is about 1 mm.; 

 in the natural state it is usually 0.6-0.8 mm., and the length rarely 

 exceeds 2 cm. Measured in cells the wings are mostly ten to eighteen 

 cells across. Ventral branching is not rare, but the normal branching 

 is dichotomous, the successive forks being usually 1-3 mm. apart. 



