40 



The Journal of Heredity 



is available. The work often comes 

 at such a time, however, in most of 

 the northern states, that dependence 

 would have tO' be placed largely on 

 greenhouse material. 



Seasonal restrictions and lack of 

 greenhouse facilities will also probably 

 limit in many cases what can be accom- 

 plished in the way of having the stu- 

 dent perform actual experiments in 

 plant Mendelism ; but while the direc- 

 tions in this respect cannot, perhaps, 

 often be adopted as they stand, they 

 are very suggestive and should help an 

 ingenious instructor to work out prac- 

 ticable plans to meet his own conditions. 

 The suggestion of having F^ seed that 

 the student can plant in order to study 

 segregation is a good one. This will 

 work out particularly well, for example, 

 with green and purple-stemmed Da- 

 turas, since the segregation of stem 

 color can, in this case, be observed in 

 the seedlings, and these can be raised 

 in large numbers in a short time in* 

 small germinating pans in an ordinary 

 room. 



The feasibility of giving the work on 

 plant hybridization (practice in cross- 

 pollination) will again depend on fa- 

 cilities and other conditions. The se- 

 lection of types would be difficult to 

 improve, but it would perhaps have 

 added much to the usableness of this 

 section if illustrations had been sup- 

 plied, showing the instruments to be 

 employed, and the methods of perform- 

 ing the operations. 



Practical work in animal breeding 

 (aside from that on Drosophila) is even 

 more difficult to bring into a regular 



laboratory course than is work with 

 plants. The suggestions along this line 

 deal with registry methods with cattle, 

 a subject which is, in most agricultural 

 colleges, included in the course in Ani- 

 mal Husbandry. It is important, of 

 course, that students interested in gene- 

 tics in relation to agriculture should 

 get this knowledge, but it would seem 

 that it would have been well to include 

 also some training in the methods of 

 keeping breeding records more particu- 

 larly for genetic uses. 



Putting out a laboratory manual, par- 

 ticularly in a new field, is a somewhat 

 precarious venture, since every instruc- 

 tor is likely to have his own ideas as 

 to material and methods ! or at any rate, 

 as previously mentioned, he is likely to 

 be limited by his available facilities and 

 the condition under which his work 

 must be given. It would, therefore, be 

 somewhat- hazardous to venture an 

 opinion as to how completely these di- 

 rections can be adopted without modi- 

 fication, but the reviewer has no hesi- 

 tation in saying that any teacher of 

 genetics, whether or not he has previ- 

 ously been offering a laboratory course, 

 will find the manual full of useful sug- 

 gestions. In places, in fact, it would 

 appear to be addressed more directly 

 to the instructor than to the student. 

 Nevertheless, if it helps to stimulate, 

 as no doubt it will, the institution of 

 laboratory work in connection with 

 courses in genetics, where such work 

 has not previously been given, it will 

 serve a most useful purpose. 



L. J. C. 



The Bureau of Crop Estimates, 

 United States Department of Agricul- 

 ture, maintains 199,384 voluntary crop 

 reporters, to whom schedules of inquiry 

 regarding crop and live-stock conditions 

 are forwarded periodically. These 



The Basis of Crop Reports 



schedules are tabulated and averaged. 

 The data thus collected and compiled, 

 supplemented by reports from the field 

 service, constitute the basis of the 

 monthly and special crop reports of the 

 bureau. 



