LITTLE EGGER MOTH — MODE OF SUSPENSION. 309 



no indications that the insect has ever broken it. These cocoons 

 are far more conspicuous than those of the Drinker Moth, and 

 are attached rather lightly to the stems of various plants. 



There is a smaller insect, popularly called the Little Eggek 

 Moth (Eriogaster lanestris), which spins a cocoon of a similar 

 structure, except that the walls are of even harder and more uni- 

 form texture, scarcely larger than a wren's egg, and of a substance 

 which looks almost as if it were made of the same material as the 

 egg. When broken, it is found to be even more brittle than that 

 of the larger insect. Owing, in all probability, to the exceeding 

 closeness of the structure, which would exclude air from the in- 

 habitant, it is perforated with one or two very tiny and very cir- 

 cular holes, which look just as if some one had been trying to kill 

 the insect by piercing the cocoon with a fine needle or pin. 



Even from the outside these perforations are visible, but they 

 are much more evident when the cocoon is opened. The object 

 of these holes is, however, conjectural, and it would be a useful 

 experiment to stop them with wax, in order to see whether the 

 inclosed insect could be developed when the air was thus ex- 

 cluded. I believe that there are none of these holes in the co- 

 coon of the large Oak-egger Moth, and if there be any such per- 

 forations, they are so minute as to escape notice. 



If the reader will refer to page 294, he will see an account of 

 certain cocoons which are made by hymenopterous insects, and 

 suspended by a single thread from the branches. In Mr. H. W. 

 Bates's work on the natural history of the Amazon Eiver, there 

 is a most interesting account of a pensile cocoon also suspended 

 by a single thread, but which is the work of a lepidopterous in- 

 sect. It will be seen that Mr. Bates was able to see the insects 

 spin the cocoon, and his account exactly tallies with Mr. West- 

 wood's conjecture as to the method by which the creature man- 

 ages to produce a hollow cocoon at the end of a single thread. 

 Mr. Bates's account is as follows : 



" The first that may be mentioned is one of the most beautiful 

 examples of insect workmanship I ever saw. It is a cocoon, 

 about the size of a sparrow's egg, woven by a caterpillar in broad 

 meshes, of either buff or rose-colored silk, and is frequently seen 

 in the narrow alleys of the forest, suspended from the extreme tip 

 of an outstanding leaf by a strong silken thread, five or six inches 

 in length. It forms a very conspicuous object, hanging thus in 



