1894 THE MIOUOSCOPE. 189 



the same mixture of Cocconema and Gomphonema as that seen 

 n my own slides) and his ingenious explanation of the phe- 

 nomenon b}' the vagaries of a rhizopod resembling Actinophrys 

 sol has much impressed me, the more so as I have myself wit- 

 nessed this creature's curious attack upon the contents of indi- 

 vidual frustules, and its emergence therefrom in the shape and 

 with the rays shown in Prof. Smith's drawing, but I am not yet 

 satisfied that the cysts of which I have got many perfectly clear 

 examples in numerous other species are purely imaginary ! 



Prof. Smith admits the difficulty of accounting for the many 

 minute frustules which abound in most mixed gatherings and 

 which bear close resemblance to the different species of normal 

 size in the gatherings. However, his paper has made me pause 

 and I am making further and more exact observations of my 

 cysts and their contents before writing further. — J. NewtoN" 

 CooMBE, Sheffield, England, October 11, 1894. 



SCIENCE-GOSSIP. 



Detecting Blood.-A chemical authority states that he has 

 discovered a method for detecting blood stains that the micro- 

 scope has failed to reveal. When the smallest drop of blood is 

 mixed wdth fifteen grammes of distilled water, and one or two 

 drops of tinture of guaiacum added, a cloudy precipitate of resin 

 is yielded, and the solution becomes slightly colored. When 

 there is further added to it a drop of etherial solution of perox- 

 ide of hydrogen, a blue color appears, which becomes deeper 

 and deeper on exposure to the air. — Science Siftings. 



RECENT PUBLICATIONS. 



Transactions of the Hertfordshire Natural History Society. Vol. 

 VII, parts 8 and 9. John Hopkinson, Editor. 



We have recently received from the Society a copy of these 

 proceedings which are issued once in two months. They are 

 beautifully illustrated with photo-engravings and contain many 

 interesting papers on general natural hi^ry. The excursions 

 to points of interest form an interesting feature of the society's 

 work. We ought to do more of such work in America. 



