68 DIRECT BENEFITS FROM MOTHS. 



has been termed the spinneret, which Reaumur sup- 

 poses to have two orifices for the extrusion of the 

 silk, which, however, the accurate Lyonnet found to 

 unite before their reaching the termination of the 

 tube ; and discovered that it was composed of alternate 

 slips of horny and membranaceous substance, the 

 one intended for compressing the filament into small 

 diameter, and the other for enlarging it at the will of 

 the animal. Its point is truncated like the nib of a 

 pen, which admirably adapts it for applying it to any 

 object. Lyonnet has given full and satisfactory 

 delineations of dissections of all the silk spinning 

 apparatus of moths. The species he selected for this 

 purpose was the caterpillar of the Goat Moth, 

 P. cossus. 



MAGNIFIED PROFILE OF THE HEAD OF THE GOAT 

 MOTH CATERPILLAR. 



I 



The spinneret is seen at a, and the throat, or 

 trachea, at b. The shape of the tube itself will be 

 better understood by the following figure, which is 

 magnified 22,000 times. 



