December 23, 1896.] 



Garden and Forest. 



519 



here just now ; the gardens are ruined by them, and the fruits, 

 especially grapes, are being fast destroyed. The pests are 

 chiefly an ant introduced from Brazil, which overruns every- 

 thing, and various species of Coccidae." A few of the Coccida? 

 and specimens of the ant were sent. The Coccidas were, 

 unfortunately, not in a condition to be determined, with the 

 exception of Aspidiotus rapax of Comstock, which was in 

 quantity on twigs and leaves of Stillingia cebifera, LinniS. On 

 the same plant were some young Lecanium, apparently L. 

 hesperidum. On Myrtus communis were some very young 

 scales, apparently of the same two species. On Sechium 

 edule a cottony mass with only fragmentary remains, and 

 puparia of some dipterous parasite. The ant I sent to Mr. 

 L. O. Howard, who writes that Mr. Pergande has determined 

 it as Iridomyrmex humilis. 



Madeira is an island where little or no attention has been 

 paid to economic entomology, but it is evident that there is an 

 ample field for research. Had there been a competent resi- 

 dent entomologist to recognize and take measures against the 

 several pests upon, or soon after, their introduction, no doubt 

 much of the injury described by Dr. Grabham might have 

 been prevented. Even in the absence of such an individual, 

 any resident of the island who may read these lines can do 

 good service by simply collecting specimens of the pests and 

 sending them where they can be determined. 



Agricultural College, Mesilla, N. M. T. D. A. Cockerell. 



A Contagious Disease of White Grubs. 

 To the Editor of Garden and Forest : 



Sir, — In connection with my notes on lawn-infesting insects, 

 published in your journal (see page 472), it may be worth 

 while to speak of some experiments made in the use of 

 a fungous disease, caused by Isaria densa, against white 

 grubs. The experiments were first made in France and Ger- 

 many, and tube cultures have been advertised for sale under 

 the name of " Rose muscardine." According to the directions 

 it was necessary to gather a lot of one hundred or more white 

 grubs and inoculate them carefully with the culture. Then they 

 were to be buried in a specially prepared bed, to remain until they 

 were properly " mummified." Then two or three hundred 

 more white grubs were to be collected, put into this same bed 

 with the mummified grubs, and after these in turn had become 

 destroyed, specimens were to be buried in the infested land 

 at intervals of a foot or so apart. If white grubs were con- 

 tinually collected and placed in the bed of infestation, a supply 

 of mummies, more or less constant in character, could be 

 maintained. It is obvious that this process, while simple 

 enough for a laboratory experiment, is altogether too compli- 

 cated for use by the owner of a small lawn or garden, and it 

 has the disadvantage of not becoming available for a consid- 

 erable time after the infestation tubes are received. By the 

 time the owner of a lawn has gathered several hundred white 

 grubs in order to start his disease-bed, it may happen that 

 there are no more of them to be killed off. Furthermore, ex- 

 periments made in Illinois in the laboratory of Professor S. A. 

 Forbes indicate that the disease loses virulence very soon. 

 It is fair to say that an effort is being made to simplify the use 

 of the germs, and it is now advised that the first culture be 

 made on boiled potatoes, which it seems will support the 

 Isaria. By planting the infected potatoes in a prepared bed 

 and covering with earth until the mass has become thoroughly 

 filled with the fungus, it can be taken out entire and spread 

 broadcast over infested lawns. The object is to distribute the 

 disease everywhere throughout the soil, that it may come into 

 contact with the white grub larvas. Even as the matter stands 

 at present, however, the use of the disease is complicated if it 

 is necessary to employ it from the cultures. If it were possi- 

 ble to purchase at a reasonable rate the dried cakes of material 

 ready to bespread upon the land, the use of this disease might 

 prove feasible. Unfortunately, however, up to the present 

 time it has not been proved that the American white grub is as 

 readily susceptible to the disease as the European, and for the 

 present, at least, resort must be had to other measures. 



Rutgers College. J- B. Smith. 



Recent Publications. 



The Survival of the Unlike : A Collection of Evolution 

 Essays suggested by the Study of Domestic Plants. By 

 L. H. Bailey. New York : The Macmillan Co. 1896. 



This is an attempt, and perhaps the first systematic 

 attempt on any important scale, to extend the theory of 



evolution to the practice of horticulture. Few evolutionists 

 have theorized on the vegetable world, speculation in this 

 field having been directed almost entirely to animals rather 

 than to plants. No American writer, at least, has ever 

 assumed any bold position in relation to the development 

 of vegetable life. Darwin studied the life of plants under 

 cultivation as well as under natural conditions, but he did 

 this primarily, and almost entirely, to gather data for estab- 

 lishing and enforcing the general philosophy of evolution, 

 and not to explain cultural practice. Nearly all that is new 

 in the art of gardening has come from direct experiment. 

 In these essays the attempt is made to attack horticultural 

 problems from the opposite side. We do not mean by this 

 that Professor Bailey advocates the abandonment of direct 

 experiment as a help to practice, but rather that this book 

 takes up facts already known as data, and then attempts to 

 explain by reasoning from these data what particular 

 lines of experiment and practice offer the greatest promise. 

 These essays, which have been read at various times before 

 horticultural societies, were prepared primarily for horti- 

 culturists. But it is plain that they were prepared also for 

 evolutionists, and in the preface to this book Professor 

 Bailey gives some reasons why he usually selected as a 

 subject for discussion before such audiences some topic 

 associated with the evolution of plants. In the first place 

 he is convinced that many of the common questions which 

 puzzle cultivators can only be answered by appealing to the 

 evidences of evolution. Again he thought that it would be 

 helpful to persons who deal with plants and animals and 

 lead a rural life to have some knowledge of modern specu- 

 lations in the evolution theory and of the methods of re- 

 search which they suggest. And finally he wished to 

 make a record of a great class of common facts which 

 have a vital relation with organic evolution, but which are 

 almost entirely overlooked by students and philosophers. 



In the first chapter of the book we find an expansion of 

 the thesis that development in the plant world has come 

 about by very slow and gradual transformation, rather 

 than by jumps or sports. This, however, is part of the treat- 

 ment of the main proposition that the fittest survives be- 

 cause it is unlike everything else. Therefore the study of 

 differences which arise from all sorts of environment, and 

 as a complex resultant of hundreds of forces from without 

 and from within, ought to be the controlling method in 

 investigating the progress of life. A new type with 

 its divergences of character from the old may find a 

 line where the resistance to expansion and growth is 

 less than it was to the parent, and therefore it spreads 

 rapidly under changed conditions. That is, the new types 

 strike out and find fields where competition is less active 

 than in the old ones. Another thesis, which is treated so 

 freshly as to make it appear new, relates to bud variation. 

 In this Professor Bailey attempts to prove that variation of 

 the bud is no more mysterious than variation of the seed, 

 for the reason that in an important sense every branch is a 

 distinct individual which has been exposed to a different 

 set of conditions, and it therefore has the power of repro- 

 ducing its essential characteristics. 



It is not our intention, however, to give any analysis of 

 the contents of the book. In fact, being a collection of 

 addresses delivered at different times and on different occa- 

 sions, it has not the consecutiveness and unity which 

 would be expected in a systematic treatise, although for 

 some purposes the book is better for its repetitions and its 

 treatment of subjects from different points of view. Cer- 

 tainly the essays must have been stimulating to the audi- 

 ences of working cultivators who listened to them, since 

 they were prepared for men brought into constant contact 

 with vegetable life, and therefore compelled to observe the 

 phenomena of vegetable growth, but without the training 

 or habit of generalizing or making deductions from facts. 

 A glance at the table of contents will show what an inter- 

 esting range of topics is embraced in the discussions and 

 will convince any one that it is a good book to put into the 

 hands of any intelligent farmer or gardener. It will give 



