Fusion- Structnn's i)i Mitcorites. 



311 



NOTE. 



The drawings on the three accompanjdug Plates were executed free-haud, 

 in preference to making use of a camera lucida. 



Had photograpliy been resorted to, tlie forms depicted would undoubtedly 

 liave been obtained with greater accuracy in outline and detail than it is 

 possible to procure, even in the most conscientious free-hand work. The 

 latter, however, offers the inestimable advantage of permitting the struc- 

 ture studied, aod this structure only, to be shown ; while photography 

 necessarily iutroducss all that lies above and beneath, and in the immediate 

 neighborhood of the object under the glass of the microscope. 



Hence, whenever on the Plates an object is drawn in the centre of the 

 field, the rest of the space being left blank, it must be understood that the 

 surrounding matter has been simply ignored in the drawing, as being 

 foreio'n to the structure studied. 



INDEX TO PLATES. 





PLATE XIX. 





igure. 



No. of Jfeteorite. 



No. of Slide. 



Diameters Magnified 



1 



2 



2 



300 



2 



2 

 (Left upper part of 1.) 



2 



1500 



3 



2 



2 



300 



4 



2 



30 



300 



5 



2 



30 



300 



6 



14 



23 



75 



7 



14 



23 



300 



8 



14 



23 



300 



9 



5 



8 



300 



