172 abstracts: botany 



CERAMIC CHEMISTRY.— r/i^ effect of certain impurities in causing 

 milkincss in optical glass. C. N. Fenner and J. B. Ferguson. 

 Journ. Amer. Ceram. vSoc. 1: 468-477. July, 19 18. 



In the manufacture of optical glass at one of the plants, a matter 

 which gave considerable difficulty for a while was the occasional produc- 

 tion of pots of glass which were affected by opalescence or milkiness. 

 The evidence indicated that the source of the trouble lay in the sulphate 

 and chloride content of the potash. The trouble disappeared when more 

 reliable methods of temperature-control were installed, by which an 

 assurance could be had of keeping the temperatures constantly at 

 1400° to 1420° C. Later, evidence was obtained which connected the 

 milkiness quite definitely with the impurities mentioned, at least as 

 regards the case under discussion, although in other cases the same 

 effect is to be ascribed to other causes. Reasons are given for the con- 

 clusion that the milkiness is caused not by the separation of sulphates 

 or chlorides themselves, but to some slight change in the physical 

 properties of the melt which permits the separation of clouds of minute 

 crystals of cristobalite. R. B. Sosman. 



BOTANY. — Naming wheat varieties. CarleTon R. Ball and J. 

 Allen Clark. Journ. Amer. Soc. Agron. 10: 89-94. February, 

 1918. 



Crop varieties should be designated by names that are short, simple, 

 appropriate, easily spelled, and easily pronounced. The multiplication 

 of names and other designations for crop varieties has been carried to 

 great extremes. Present designations may be classed as follows: 

 (i) Names, as Fultz or Kubanka; (2) descriptive phrases, as Early 

 Red Clawson; and (3) numbers, as Minnesota no. 162. The existing 

 confusion in names renders difficult the interpretation of published 

 results of experiments. This confusion occurs in two principal ways: 

 (i) The same name is applied to very different varieties in different 

 parts of the country; (2) the same variety passes under several different 

 names in different parts of the country, or even in the same part. 



It is desirable to prevent a continuation of such practices and to 

 attempt a solution of the problems already existing. Accordingly, a 

 brief but comprehensive code of nomenclature has been formulated. 



code of nomenclature 

 I. Eligibility to naming. No variety shall be named unless (a) 

 distinctly different from existing varieties in one or more recognizable 



