NATURAL SCIENCES OF PHILADELPHIA. 3G9 



A quantitative Bausch analysis of this rock I did not undertake, 

 because every specimen has probably a different composition, due 

 to the unequal distribution of the S'fibiaferrite. 



As I liave not seen the rock in situ, I cannot say whether there 

 occurs more antimony in tlie form of Stibiaferrite or as Stibnite ; 

 at any rate, it is worth while for the managers of the mine to 

 make this inquiry' and let us knoAv. 



The Stibnite had on one spot a cavity containing about four 

 crystals of very small size. Viewed under the microscope one 

 white crystal had the form of Yalentinite, as figure 119 in Dana's 

 Desc. Min., which crystal was attached to a crystal of Stibnite, 

 showing the gradual change of the latter into the former. Another 

 crystal appeared to be a perfect cube, which may be Senarmontite. 



I first saw the specimens in the collection of John C. Traut- 

 wine, C. E. This gentleman called m3'- attention to the peculiar 

 j-ellow mineral on the Stibnite, which he presumed to be new ; the 

 presumption is correct so far as my investigation goes, and I here- 

 with return thanks for the specimens received. 



October 28. 



The President, Dr. Ruschenberger, in the chair. 



Twenty-two members present. 



The following paper was presented for publication : " Descrip- 

 tions of Mexican Ichneumonidae." By C. T., Cresson. 



The following gentlemen were elected members : Jos. C. Wright 

 and Dr. G. T. Barker. 



Charles V. Rilej', of St. Louis, Mo., was elected a Correspon- 

 dent. 



November 4. 

 The President, Dr. Ruschenberger, in the chair. 

 Thirty-five members present. 



November 11. 

 The President, Dr. Ruschenberger, in the chair. 

 Nineteen members present. 



Mr. Thomas Meehan desired to correct an error made in his 

 remarks on the Exceptional Conditions of Forest-seed Germina- 

 tion, to which Mr. Sereno Watson liad kindly called his attention. 



