20 



AMERICAN BEE JOURNAL. 



THE NEKVOUS SYSTEM. 



Let us now turn our attention to the 

 nervous system. By referring to the 

 engraving you will see parallel and 

 medial lines passing the entire length of 

 the bee, and finally communicating with 

 the brain, A. Along at irregular inter- 

 vals will be seen thickened masses, 

 called " ganglia." These are really little 

 brains, and, as in our own bodies, preside 

 over the involuntary muscles. The 

 largest ganglion is the brain, at A, and 

 is the seat of voluntary action and 

 intelligence. 



One is surprised in reading through 

 chapters 10 and 11 of Mr. Cowan's 

 work, how thoroughly scientists have 

 studied the structure of the nervous 

 system as found in the bee. Even the 

 tiny brain has been dissected, and its 

 various functions pointed out— that is, 

 what parts communicate with the 

 antennae, what part with the eyes, etc. 

 I was greatly interested, in looking over 

 the sizes of the different brains found in 

 different insects. I quote here a para- 

 graph from page 70 : 



"It is generally admitted, that the 

 size of the brain is in proportion to the 

 development of intelligence; and Dujar- 

 din, who made careful measurements, 

 gives the following sizes : In the worker 

 bee the brain is 1/174 of the body; in 

 the ant, 1/286 ; the ichneumon, 

 1/400; the cockchafer, 1/3920; 

 hedytiscus, or water-beetle, 1/4200." 



In man the proportion is 1 to 40, I 

 believe ; but we all know that he is of 

 the very highest order of intelligence. 

 However, we are not very much sur- 

 prised to learn that the bee has the 

 largest brain of any of the insects, 

 exceeding by far even that of the ant, 

 whose intelligence we have admired over 

 and over again. 



THE RESPIKATOEY SYSTEM. 



• It is also interesting to inquire how 

 the bee breathes, and chapter 8 points 

 out to us the wonders of the nervous 

 system in the bee. • By referring to the 

 engraving given, we observe a couple of 

 large air-sacs, called the "trachea," 

 which corresponds somewhat to the 

 lungs. These are located on either side 

 of the abdomen, as at T. They are 

 divided and subdivided into smaller 

 trachea, and in turn ramify all through 

 the entire body. 



Instead of fresh air being received in 

 at the mouth, as with us, fresh supplies 

 are admitted through 14 little mouths, 

 called "spiracles." Ten of these are 

 located on the abdomen — five on each 



side — and are situated just about on the 

 margin of the scales, between the dorsal 

 and ventral segments. Four others are 

 situated on the thorax, or waist, two on 

 each side. 



You may; therefore, decapitate a bee 

 and it will continue breathing as before. 

 If you place a pencil dipped in ammonia 

 near its body, the headless insect will 

 struggle to get away ; and if the pencil 

 touches its feet, the ganglia already 

 spoken of communicate the sensation to 

 the other ganglia, and at once all the 

 feet come to the rescue to push off the 

 offending object, or, it may be, to take a 

 closer hold so the sting may do its 

 work. 



Besides that, if bees are daubed with 

 honey, they will die very soon from 

 strangulation, because these little 

 mouths or spiracles are closed. A bee 

 may swim around in a trough of water, 

 and, though its head be entirely out, it 

 will drown just the same, because these 

 spiracles, or breathing-mouths, are 

 submerged. 



On a hot day, if the entrance of a hive 

 be closed, the bees will soon begin to 

 sweat ; and, thus becoming daubed, the 

 delicate spiracles are closed, and the 

 bees die. 



EGYAL JELLY, AND WHAT IS IT ? 



Nothing in the book interested me 

 more than the discussion in chapter 18 

 in regard to the royal jelly. Cheshire 

 insists that it is secretion from one of the 

 glands ; but Prof. Cook has maintained 

 that it is the product of the chyle- 

 stomach ; and Mr. Cowan proves con- 

 clusively that this is the right view, and 

 and eminent authority is not wanting to 

 sustain them. 



This chyle is produced in what is 

 called the chyle-stomach, shown at L, 

 in the engraving ; and worker larvae are 

 fed on this concentrated food for three 

 days, after which they are weaned. "On 

 the fourth day this food is changed, and 

 the larva is weaned ; for the first pap 

 has a large quantity of honey added, but 

 no undigested pollen, as Prof. Leuckhart 

 had stated. The drone larvae are also 

 weaned, but in a different way ; for, in 

 addition to honey, a large quantity of 

 ■pollen is added after the fourth day." 

 And right here I cannot do better than 

 quote from Mr. Cowan : 



"Microscopic examination showed 

 that, in the queen and worker larvae, 

 there was no undigested pollen ; whereas 

 in the drone larvae, after the fourth day, 

 large numbers of pollen grains were 

 found. In one milligram, no less than 

 15,000 pollen grains were counted, and 



