556 



THE POPULAR SCIENCE MONTHLY. 



interesting and valuable facts respect- 

 ing it. As will be noticed by the care- 

 ful reader, he speaks of what he has 

 himself observed, and much of what he 

 says will be new to all but experts, as it 

 has only recently been recognized by 

 science. His observations establish the 

 fact that most of the decay of wood, in- 

 cluding what was formerly called ere- 

 macausis or slow combustion and dry 

 rot the name now representing the 

 result, whereas it was formerly held to 

 describe the cause is produced by the 

 growth of mycelia of fungi, ' which 

 effect the disorganization of the wood- 

 cells. The figure on page 438, which 

 is from a photograph, tells more on 

 this subject than many pages of letter- 

 press could do. Some of the fungi de- 

 scribed and figured by Mr. Dudley are 

 old acquaintances to frequenters of the 

 woods who have observed the curious 

 forms of their pilei on stumps and 

 logs, and have supposed them to be 

 fruits of rottenness. Mr. Dudley ex- 

 hibits the more essential parts of these 

 fungi, the mycelia penetrating and in- 

 terpenetrating every part of the inte- 

 rior of the wood, and generating the 

 rottenness of which the pilei are the 

 sign. Some suggestive observations 

 may also be found in the article con- 

 cerning the relations of moisture to the 

 growth of fungi. Mr. Dudley will con- 

 tinue the subject in another article, 

 with some practical suggestions found- 

 ed on the results of his investigations. 



"We print in this number of the 

 " Monthly " the last of the series of 

 papers by Mr. David A. Wells upon the 

 economic condition of Mexico. Accu- 

 rate information of a country with which 

 we must inevitably come into intimate 

 political and financial relations is in the 

 highest degree desirable, but has here- 

 tofore been very difficult to obtain. 

 Mr. Wells whose competency to per- 

 form the task he has undertaken will 

 be questioned by no one has done a 

 valuable service, making us acquainted 



with the actual condition of this but 

 little-known country. As he says, the 

 pictures usually drawn of the natural 

 resources of the country and its future 

 possibilities have been rose-colored in 

 the extreme. He finds, on the contra- 

 ry, that the country is almost hopelessly 

 poverty-stricken to such an extent, 

 indeed, that the problem of a stable 

 government is beset with the greatest 

 difficulties. With an army consuming 

 a third of the revenue of the state, a 

 system of internal tariffs between each 

 of the States, or political divisions com- 

 posing the republic, and with an almost 

 entire absence, until very recently, of 

 means of communication between dif- 

 ferent parts of the country, anything 

 like industrial progress or political sta- 

 bility has been out of the question. His 

 study of the country does not lead him 

 to any very hopeful prediction of its 

 future. Its natural conformation that 

 of a great table-land, devoid of naviga- 

 ble streams, with a strip of coast-land 

 on either side which can only be reached 

 by abrupt descents is unfavorable to 

 the material development of the coun- 

 try ; while the character of the people, 

 their extreme poverty, and the enor- 

 mous load of public debt, are almost 

 insurmountable obstacles to any great 

 degree of prosperity. In our own in- 

 terest, as well as that of Mexico, he be- 

 speaks a kindly and helpful attitude on 

 the part of this country toward the 

 weaker republic, and his words are 

 well worthy the attention of all Ameri- 

 cans who desire to see their country 

 without reproach in all its internation- 

 al relations. 



LITERARY NOTICES. 



Teacher's Hand-Book of Psychology. By 

 James Sully, M. A. New York : D. Ap- 

 pleton&Co. 1886. Pp.414. Price, $1.50. 



In the present work Mr. Sully has at- 

 tempted to reduce and simplify the state- 

 ment of scientific principles contained in 

 his former and larger work, " The Outlines 

 of Psychology," and to expand their prac- 



