460 INSECTA. 



monly seen in the insect, having a ganglion within the abdomen ; and 

 when it passes behind the oviduct, there are other ganglions. 



Of their Oil. — They have an oil, or rather fat, in the inside of the 

 abdomen, which is in flakes, or very small cells, something like the 

 marrow, only not so firm. It is fluid in the summer months ; and if an 

 humble-bee is opened and allowed to remain in spirits in warm weather, 

 the oil escapes from cells and swims on the top : but this appears to be 

 principally the case with the bees of the same summer ; for in the 

 queen, which is a bee of the last summer's breeding, the fat is not so 

 oily, is of a light brown, and less transparent ; which is one way of 

 knowing the queen of the hive in which the following summer's queens 

 are formed. Thus, the fat seems to change in the winter ; for those 

 which come from their hiding-places in May, have the remaining fat 

 yellow, and much less in quantity. When collected and dried on paper, 

 the paper burnt bright wben it came to that part. In the month of 

 September the females are full of it. 



Of their Voice. — The humble-bee has several sounds ; one is when 

 they fly, which is round, full, and uniform : it is probably caused by 

 the wings striking against the air ; but they can form various sounds 

 independently of the common air. They have a sound when the wings 

 are closed, but moved with short vibrations, which is probably caused 

 by the air expelled from the air-cells striking the wing at the time : 

 this is a kind of peevish noise. They can make nearly the same noise 

 when I could not observe any motion in the wings. I have also 

 observed them to make a hiimming noise when no motion could be 

 observed in the wings. They can make a noise by shaking their heads : 

 I suspect this is done by throwing out the air from the air-vessels at 

 the time that the head is in motion, which probably has the same effect 

 as the vibration of the glottis in the human subject ; and there may be 

 even some analogy with the motion of the head, in the human, in per- 

 forming a shake. It is possible, as they have a number of tracheae, 

 that each may have a sound peculiar to itself. 



Of the Breeding-cell and Maggot. — The cell in which the humble-bee 

 lays its egg, is very small, and is made of a waxy substance, which 

 the maggot eats ; and, as it eats on the inside, the old bee is laying 

 more and more on the outside ; so tbat the cell and animal increase 

 together equally. "When the maggot arrives at its chrysalis state, it 

 lines this cell with its silk, making a membranous part like that of the 

 wasp, on the outside of which is the remains of a soft waxy substance 

 very irregularly placed. 



In the maggot, the stomach passes almost the whole length of the 

 body ; and, at the lower part, it becomes small and makes a turn upon 



