November 17, 1904] 



NA TURE 



6i 



nerican of October 22 contains the 

 raccoon-dog from northern Japan, in 

 fical Park, which is regarded as repre- 

 and is accordingly named Nyctereutes 

 raccoon-dog of Japan and China is 

 d to the true dogs, but with a marked 

 re to a raccoon. If the New York 

 tes the existence of a white species of 

 t will be of considerable zoological 



The Scientific At 

 portrait of a white 

 the New ^'ork Zoolof; 

 senting a new species 

 albus. The ordinary 

 an animal closely allii 

 superficial resemblan 

 specimen really indie; 

 raccoon-dog, the fac 

 interest. 



Is the second part of the Bergen Museum Aarbog for the 

 current year Prof. G. O. Sars describes a small crustacean 

 (Paracartia gram') recently discovered in the oyster-beds of 

 western Norway which is of great interest from the point 

 of view of distribution, since the only other known repre- 

 sentative of the genus inhabits the Gulf of Guinea. The 

 author considers that the creature reached Norway from 

 the south during a warm period, and that it survives on 

 the bays of the west coast owing to the circumstance that 

 a superincumbent layer of fresh water renders the subjacent 

 salt water unusually warm. The same explanation accounts 

 for the prolific oyster-beds on this coast. 



I.v the November number of the Century Magazine Prof. 

 H. F. Osborn publishes in extenso the lecture on the evolu- 

 tion of the horse in America which he delivered at the 

 recent Cambridge meeting of the British Association. 

 Omitting reference to that portion of the article devoted 

 to the origin of the Equida^ generally, we may mention that 

 the author regards North .America as the ancestral home 

 of the genus Equus, the American horses passing into South 

 -America by way of Panama, and into .Asia by a land-bridge 

 across Bering Strait about the early or middle portion of 

 the Pliocene period, giving rise in the latter area to the 

 .Siwalik horses (which, by the way, are not later than older 

 Pliocene age). Horses of all kinds died out both in North 

 and in South .America, according to the author's belief, 

 before the European conquest. The American Miocene and 

 Pliocene horses are considered to have been striped ; but 

 the splitting of Ecjuus into the true horses, asses, and zebras 

 probably took place in the Old World. Przewalski's horse 

 of Mongolia is regarded as representing the ancestral stock 

 of the ordin^iry horses of the Old World, the long manes 

 and tails of the latter being probably due in part to domesti- 

 cation. On the other hand, the author accepts the view that 

 the blood-horse may have had a different ancestry, although 

 he does not refer to its suggested derit-ation fr'/m the Indian 

 Equus sivalensis. 



Some interesting experiments in blasting tree butts with 

 gellignite — a safety explosive — have recently been carried 

 out at Lord Leigh's Stoneleigh Abbey Estate, near Kenil- 

 worth. The usual boring was made and filled with the 

 explosive. An electric detonator was used which enabled 

 the operator to retire under cover at a safe distance. The 

 butts operated upon were of various sizes and species, but 

 in each case the method was found to give satisfactory 

 results. It is also claimed to combine efficiency with 

 economy. 



The comparative age of the different elements of the flora 

 of eastern North America forms the subject of a paper by 

 Dr. J. W. Hashberger in the September issue of the Pro- 

 ceedingt of the Philadelphia Academy. Most of the flora 

 cannot be older than the close of the Glacial period, which, 

 from the rate of cutting of the Niagara g^wge, is estimated 

 to hat'e occurred not more than 15,000 years ago. Some of 

 •'- Mements may, however, be much older, since they may 

 NO. 1829, VOL. 71] 



be the descendants of boreal plants which flourished on un- 

 glaciated areas in the midst of the ice-sheet. Apart from 

 these, there was firstly a wave of plant-life from the skirts 

 of the ice-sheet. This was followed by a northern wave, 

 many of the species of which, forming the bog-plants of 

 the old Glacial lakes, soon occupied the tundra left by the 

 ice ; the conifers developed later, and restricted the bog- 

 flora. Hence came the modern bog and swamp floras, 

 while the existing Poccona flora is due to a third invasion. 



The work of the Forestry Bureau of the United States 

 Department of ^Agriculture stretches far afield, and the 

 forests of the Hawaiian Islands form the subject of one 

 liulUtin by Mr. W. L. Hall, while Mr. W. L. Bray in 

 another reviews the forest resources of Texas. The 

 succession of the forests in Texas indicates that their dis- 

 tribution is primarily influenced by the amount of rainfall, 

 and only secondarily by the nature of the soil. A remark- 

 able instance of the spread of a successful type is furnished 

 by the mesquite, Prosopis glandulosa, which has spread 

 from the Rio Grande eastwards across the Rio Brazens, and 

 northwards into the adjoining States of Oklahoma and 

 Kansas. In the Hawaiian Islands a mesquite, although an 

 alien, has established itself as a pure forest from sea-leve! 

 to an elevation of several hundred feet, and is regarded an 

 a valuable asset, because, in addition to the fuel and prists 

 obtained from the wood, the pods furnish excellent f<x;d for 

 stock. 



Ik view of the difficulties of obtaining zygospores of 

 species of Mucor and allied genera, considerable importance 

 attaches to a paper — " Sexual Reproduction of the Muror- 

 ineae," by Mr. A. F. Blakeslee — which is published in the 

 August number of the Proceedings of the American Academy 

 of Arts and Sciences. The author found that the greater 

 number of these fungi failed to produce zygospores in pure 

 cultures, but some would do so when a mass of spores taken 

 from an impure culture was sown together. This suggested 

 that in the latter cas»; zygospores were pro^luced from 

 different mycelia or plants, and eventually experiments 

 demonstrated that two different strains, which may be re- 

 garded as a (+) and a (— ), were required ; thus two groups, 

 the heterothallic and homolhallic, are distinguished. 

 .Sporodinia is homothallic, Phycomyces, Rhizopus, and 

 several species of Mucor are hetf^rothallic. Differences of 

 colour, luxuriance and duration of conjugating ability were 

 noted, but the most interesting results obtained were in- 

 cipient attempts at hybridisation by opposite strains of allied 

 heterothallic forms. 



We learn from the Standard that, under the auspices of 

 the Meteorological Council, a new observing station for 

 IxmA'm has just been established in St. James's Park. The 

 station is situated in an open spot a few yards distant from 

 the iron railings bordering on the Horse Guards Parade, 

 and is equipped with a set of theTmt>metwf>, mounted in a 

 Stevenson screen, and two rain gauges — one of quite an 

 ordinary kind, the other a self-registering gauge of the 

 pattern designed by Mr. F. L. Halliwell, of Southpf/rf. 

 Just within the park railings are placed two ornamental 

 wooden frames, one containing, for the previous twenty- 

 four hours, automatic records of bright sunshine, of rain- 

 fall, and of temperature, all made in Westminster ; the other, 

 copies of the latest weather charts and forecasts prepared at 

 the Meteorological Office. 



We have receii-ed a copy of the results of the magnetical 

 and mete»vrological observations made at the Royal Alfred 

 Observatory, Mauritius, in the year lyji. The obtervatory 

 has a conjplete equipment of instruments recording photo- 



