NOVEMBEK 9, 1917] 



SCIENCE 



459 



hits died out in some way, since it no longer 

 erists in the island. 



A further objection to the hypothesis lies in 

 its particular application to the flora of New 

 Zealand. On the basis of the soundings, Pro- 

 fessor Willis believes that the land bridge over 

 which came the original plant jKDpulation of 

 the islands entered at about the center of the 

 chain. He presumably refers to the strip of 

 shoal water running northwesterly from New 

 Zealand toward Australia, on which stands 

 Lord Howe Island. On the assumption that 

 all the original invaders entered at this central 

 point and spread north and south, and that in 

 doing so they followed the rule of " age and 

 area," Professor Willis makes and verifies a 

 series of predictions as to the disposition of 

 the flora to-day. His whole argument hinges 

 on the existence of an original central point of 

 entry and dispersal. It neglects entirely the 

 evidence that a large and characteristic ele- 

 ment of the New Zealand flora entered the is- 

 lands not from Australasia on the west, but 

 from the antarctic regions to the south. 

 Hooker, Wallace and Cheeseman, the foremost 

 authorities on antarctic floras, state their be- 

 lief that, even if there was never a complete 

 land bridge from the southern extremity of 

 New Zealand to the antarctic continent, there 

 was at least a considerable southward exten- 

 sion of New Zealand at one time (for which 

 there is also evidence on the ocean bottom) 

 over which the " antarctic types " came north 

 and entered it. If the southern tip of New 

 Zealand was thus also a center of entrance and 

 dispersal for a large floral element. Professor 

 Willis's observations are far from supporting 

 his hypothesis. He notes particularly the 

 scarcity of endemic species at both the north 

 and south extremities of the islands, and 

 points to this fact as convincing confirmation 

 of his views, since (assuming a single central 

 point of dispersal) the extremities would be 

 populated last and would have produced as yet 

 but few endemics. But assuming a second 

 point of entry, at the southern extremity of the 

 islands, we should expect to find there to-day, 

 if the ■' age and area " hypothesis is true, a de- 

 cided bunching of endemic species. Either the 



hypothesis is incorrect, or the commonly ac- 

 cepted theory as to the dispersal of the ant- 

 arctic floras is erroneous. 



Against Professor Willis's hypothesis are 

 therefore to be urged (1) that it disregards im- 

 portant factors other than age which deter- 

 mine area of dispersal; (2) that the conclu- 

 sions which it necessarily implies as to the an- 

 tiquity of certain plant types are opposed by a 

 preponderance of evidence; (3) that, contrary 

 to its expressed assumption, many species are 

 becoming rarer and are " dying out " ; and (4) 

 that it fails to explain the distribution of the 

 New Zealand flora. 



There are doubtless a large number of spe- 

 cies which are still extending their ranges and 

 for which Professor Willis's hypothesis holds 

 good. Many persons will also sympathize with 

 his chief contention, that natural selection 

 can not fuUy explain the origin of endemic 

 species and genera; and a few will share 

 his belief in the frequency and importance of 

 very wide mutations. The problems involved 

 in the origin, dispersal and extinction of spe- 

 cies, however, are evidently far too complex to 

 be covered by any single inclusive hypothesis 

 like that of " age and area." 



E. W. SiNNOTT 



Connecticut Ageicultubal College 



erasmus darwin and benjamin franklin 

 To THE Editor of Science : Eef erring to the 

 Notes on Erasmus Darwin and Benjamin 

 Franklin in Science of September 21, last, on 

 page 291 near the bottom of Coliman 1 is the 

 remark that 



Even as far back as 1772 some one was puzzling 

 over the idea of making a phonograph. 



He quotes Dr. Darwin as saying: 



I have heard of somebody that attempted to 

 make a speaking machine, pray was there any 

 truth in such reports? 



The " speaking machine " referred to was 

 not a phonograph for reproducing speech, but 

 a machine which could talk of itself. There 

 was an effort to make such a machine, which 

 the writer of the article quoted seems not to 

 have heard of. This effort was continued 



