The Microscope. 19 



brittle star fish (Ophiocoma neglecta), beautifully shown under dark 

 field illumination. 



At the next table Dr. J. H. Stallard had a fine array of seven 

 microscopes under which were arranged slides illustrative of the 

 structure of normal and also of diseased arteries. The various 

 tissues had been skillfully differentiated by various staining pro- 

 cesses, and the distinctive features of each slide were carefully 

 explained by the exhibitor. 



The elegantly sculptiu'ed egg-cases of the house-fly were shown 

 by William Payzant, and their beauty was a revelation to most of 

 the spectators. The same gentleman exhibited a slide of the pretty 

 little " brine shrimps" from the evaporating pans of the salt works 

 near Alameda. 



The next exhibitor, W. F. Myers, showed a slide on which the 

 delicate and beautiful structure of the mosquito was effectively dis- 

 played. He also exhibited an attractive mount of red marine algse. 



L. M. King was announced to exhibit living rotifers, but at the 

 last moment these were so disobliging as to die. In their place the 

 slide contained a fine example of the larva of the day-fly {Ephemera 

 vulgata), which was examined with the deep interest always excited 

 by living organisms of this kind. 



An exhibit resembling the most delicate frost work was shown 

 by A. S. Brackett. It consisted of the beautiful crystals of muriate 

 of cocaine, strikingly disjjlayed on a dark ground. A neat placard, 

 giving the name, derivation, uses and chemical characteristics of 

 this salt, was a commendable feature of this exhibit. 



Perhaps the most unique object on the entire list was that 

 shown by Prof. Hanks. It was an insect of a species now extinct, 

 perfectly perservod without the least apparent distortion, in a block 

 of amber, wherein it had rested for untold ages. As compared with 

 this perfect specimen of nature's embalming, the mummy of 

 Egypt's most ancient King is a thing of yesterday. 



Henry C. Hyde's exhibit consisted of the blood-red crystals of 

 platino-cyanide of magnesium, selected diatoms shown with dark- 

 ground illumination, and the resplendent scales of the Brazilian 

 diamond beetle. A noteworthy feature of the exhibit was that each 

 mount was illuminated by a minute electric incandescent lamp, 

 attached to an arm with universal movement. The light was shown 

 to be perfectly manageable, intense in quantity, and soft and pure 

 as to quality. To the microscopists present, this exhibit was of es- 

 pecial interest. 



