1893.] MICKOSCOPICAL JOUKNAL. 57 



added some concentrated hydrochloric acid. The disengaged 

 chlorine destroys the tatty matter, which then disappears by wash- 

 ing in water. Bottles that have contained resinous substances : 

 Wash with potash or soda and rinse with alcohol. Bottles hav- 

 ing contained essences : Wash with sulphuric acid, then with 

 water. 



BIOLOGICAL NOTES. 



Bees in Cold Weather. — A colony of bees rarely dies from 

 cold, but it may be weakened very seriously if proper precau- 

 tions are not taken. Fully as important as warmth is dryness; 

 dampness in the hive will work much mischief, and it should 

 be seen that the hive is dry, and kept in a dry place. Fre- 

 quently in cold weather sudden gleams of sunshine tempt the 

 bees out of their hives in great numbers, when they become 

 chilled, fall to the ground, and, being unable to regain the hive, 

 perish. The sun shining upon snow appears to be a special 

 temptation to bees to leave the hive. The zig-zag entrance pro- 

 vided to some frame-hives is most effectual, on account of its 

 form, in preventing the rays of the sun entering. 



Rapid Multiplication. — Bacteria, in a barrel of sweet apple- 

 juice, propagate at such a rate that were the visible universe a 

 barrel of apple-juice, these micro-organisms would fill it, 

 13,000,000 of them in every cubic centimeter. — Stephens. 



DIATOMS. 



A New London Dealer. — We have received from Barbour 

 Bros., Cromwell House, London, two of the neatest slides which 

 we have ever seen. They consist of diatoms, the first, Aulaco- 

 disciis maj-garitaceus^ from Peru, and the second, Coscinodiscus 

 diorama^ from San Redondo, Cal. They were sent to us in a 

 fine morocco case, and got into the country without any question 

 being raised by the customs people. We understand that the 

 Barbour Bros, sell a great many of these slides at $3.3:^ per dozen 

 in England, and we see no reason why they should not sell here 

 also, if properly catalogued and advertised. 



First-class slides used to sell in this country at a considerably 

 higher price than this — perhaps too high to induce many sales. 

 About this price, whicli is less than 30 cents each, no one can 

 complain. In lots of 144, the price of which is £4 sterling, they 

 come at only 13^ cents each. We shall be glad to see tbe cata- 

 logue of what Barbour Bros, have for sale. 



