88 THE AMEKICAN MONTHLY [April, 



they share with other animals, such as the toad and the snakes. But 

 the method of change in unique. Any one who has noticed the claws 

 of the crayfish or lobster would be likely to say that it was impossible 

 that the mass of tissue contained within them should be drawn though 

 the slender joints which unite the claw with the body as one might with- 

 draw the hand from a glove. This is exactly what they do, however. 

 It is not often that one may see the piocess, and it was I piesume an 

 unusualh- good fortune which enabled me to seethe last part of this 

 curious disrobing. The integument of the crustaceje and their relatives 

 is so hard and unyielding that increase in size is impossible in the or- 

 dinary way. It is provided for either by all growth occurring before 

 the adult form is assumed or by this periodical change. When the 

 old skin is to be cast off some secluded place is chosen if such 

 can be found. The animal goes through a series of strange contor- 

 tions, wringing the claws about like the hands of one stricken with 

 great agony. Head and tail are drawn violently together which 

 would in a more flexible animal hump the back with force. Some- 

 times several of these paroxysms occur iDcfore a long slit appears down 

 the middle of the back. Through the slit appears the lighter brown of 

 the new integument. At this point I surprised my captive and stayed 

 with him until the change of raiment was completed. 



The change is usually made in the night. Happening to approach 

 with a lamp the aquarium where I had a number of crayfish confined 

 I looked in upon them and found one in the condition stated. I was 

 obliged to wait nearly an hour before it went on with the process. The 

 next step seemed to be the release of the great clav\"s. It was comical and 

 painful to see the poor creature tug and strain. Suddenly, while atten- 

 tion was turned to the claws, the antenna and other adjacent parts slipped 

 neatly out and the head of the animal popped up through the slit in his 

 back. He then took another rest. The animal next worked to release 

 the claws, leaning back upon the tail and pulling steadily. The claws 

 stuck hard, but with a final twist they were released. After a short 

 rest the animal easily released the remaining legs and then seemed to 

 walk forward, withdrawing the abdomen from its old casing with 

 scarcely an eflbrt. 



Beside the habits above noted there are several others of much interest 

 to the patient obsei^ver. 



Biological Labokatokies, Carleton College, Mar. ii, 1889. 



Genuine and Manufactured Honey. — Worthington G. Smith, of 

 Pittsburg, announces that genuine honey can be readily distinguished 

 from manufactured honey by the microscope. The former has few or 

 no sugar crystals and abounds with pollen grains, while the imitations 

 have little else than these crystals, with rarely a trace of poHen grains. 

 The honeyed taste of the manufactured article, he thinks, may come 

 from honey-comb or beeswax being mashed up with the article used in 

 the manufacture. Each class of plants has its own specific form of 

 pollen grain. Any one conversant with this branch of botany could tell 

 from what part of the world the honey came by studying the pollen 

 grains that it might contain. 



Henry Mills, of Bufialo, N. Y., died February 7. in Chattanooga, 

 Tenn., of pneumonia. He was a member of the American Society of 

 Microscopists. 



