SUPERFAMILY TINEOIDEA 109 



on the part of the little caterpillar that is the maker of it and one 

 would not be able to imagine how it could have made them. This 

 the caterpillar must teach us, and it is only by discovering it in 

 the labor itself that one can understand how it succeeds in spinning 

 so pretty a cocoon. I have been fortunate enough to observe one 

 of these caterpillars at the time when it began to work at the con- 

 struction of its cocoon and I am going to make known that which 

 it made me see, as clearly as I possibly can and in as much as the 

 very small size would allow. 



I will remark first of all, and it is a thing worthy of attention 

 and uncommon, that until the caterpillar had completed a half 

 of the cocoon it remained entirely outside of it. We know that 

 ordinarily caterpillars enclose themselves in the cocoons at the 

 same time that they work at them, that in proportion to the prog- 

 ress of the construction of the cocoon the body of the caterpillar 

 becomes more and more covered. But our little caterpillar 

 proceeds quite otherwise. It lays first, so to speak, the founda- 

 tion of one of the ends of the cocoon that it intends to spin, it 

 adds new threads to this little beginning, and other sets of threads 

 to these and so on. As the work advances the caterpillar moves 

 backward, and its body remains nearly in a line with the cocoon 

 and entirely outside of it. It touches only with the head and the 

 horny legs the edge of the cocoon. 



When half of the cocoon, or to speak more correctly, half of 

 the outside layer, is completed, the caterpillar stays its work for 

 some moments. W^e notice that it then enters head first into this 

 half -cocoon. It next turns around in it by doubling its body. . . 

 Finally it comes into a reversed position so that then the posterior 

 part is found in the small or pointed end. ... of the started 

 cocoon and the head and the anterior part of the body is outside 

 of the half -cocoon. 



Next it begins to work at the other half of its cocoon. At a 

 distance from the edge of the half-cocoon about equal in length 

 to this same, it begins to spin the pointed end of the other half; 

 the length of the body serves it as a measure for not beginning this 

 half at too great a distance away. It spins this new portion in 

 the same manner as the first. As the work advances it draws the 

 head back; but as the posterior part of the body is in the finished 



