438 Evolution and Distribution of Fishes 



The peculiar genus Gunnera that has no near living 

 affinities, consists of about twenty species, the ancestors of 

 which probably evolved in the Peruvian-Andean region and 

 spread southward to N. Zealand — where now are four 

 species — thence to Tasmania, Australia, and ultimately 

 Java, where a striking and decidedly evolved species is 

 found. A somewhat similar distribution is seen in the well 

 known garden genus Fuchsia. Originating, we would con- 

 clude, in some centre not far removed from that for Gun- 

 nera fourteen species occur in Ecuador and Columbia, a like 

 number in Mexico and from Peru southward, three are 

 Brazilian, five extend from Chile to Fuegia, while three 

 are found in N. Zealand. One might also insert here 

 Muehlenbeckia adpressa and Euphrasia antarctica as simi- 

 larly distributed with the above. 



Even more remarkable is the highly modified umbelli- 

 ferous Crantzia with only one existing species C. lineata. 

 This "is a native of the United States and Mexico, the 

 Andes of N. Grenada and Peru, Chile and the Falkland 

 Islands, Tasmania and Victoria," as well as N. Zealand. 

 Many other similar facts might be cited. 



But the existing flora of Tristan da Cunha and Gough 

 Island, of Marion and Crozet Islands, even of distant 

 Amsterdam Island, that is about 5000 miles from Tristan, 

 and about 3500 from S. Africa, while indicating in some 

 of their plants such wide extension as is outlined above, 

 include also species that must have passed over from S. 

 Africa directly. Thus the arborescent Phylica arhorea is 

 most suggestive. Hooker (269:474) says: "The genus 

 Phylica consists of some Gz, species the headquarters of 

 which are S. Africa, a few are Madagascarian, one is 

 peculiar to St. Helena, and the only other is the subject of 

 this notice." He then points out its presence in Tristan da 

 Cunha, and as it had years before been found in great 

 abundance on Amsterdam Island he regarded such as "a 

 most singular fact, considering that about 5000 miles of 

 ocean intervene between these oceanic specks of land." 



One might enlarge on the genera Cotula, JVahlenbergia, 

 Sehaea, and Mese7nhryantheviiim that are typically S. 

 African genera. But the myrtaceous genus Metrosideros, 



