628 0. B. HARDENBEUO. 



exposed feeders, are not rudimentary, as mio-ht be supposed, 

 but ai-e well developed and provided with hooks which are 

 strongly curved and sharply pointed so as to hook into the 

 silken lining of the bag. Nevertheless, the legs have become 

 so short as to be entirely useless for locomotion Avhen the 

 creature is removed from its bag. 



The bagAvorm caterpillars are very tidy in their habits. 

 When we open one of the bags we find the inside always dry 

 and scrupulously clean. Ejecta and cast skins are removed at 

 once, as the presence of excrement and larval skins would 

 favour the development of fungi and decay with the slight 

 degree of moisture always present in the bag, due to the 

 emanations of the living occupant. 



Excessive moisture is their greatest enemy and quickly 

 proves fatal to them. We thus find that the bagworms (at 

 least such as we have had occasion to observe more closely) do 

 not feed during a rain or mist, but they Avill postpone their 

 meal until the foliage has dried. If the weather conditions are 

 such that they are forced to feed during the rainy weather — 

 and the young lai'vee especially cannot stand a fast of long' 

 duration — we find that a disease of a bacterial nature quickly 

 appears amongst them with disastrous results. This may be 

 due to two causes : (a) the wet food may not agree with them 

 and cause digestive disorders, as a result of which the 

 evacuations become fluid and the inside of the bag becomes 

 soiled, since they cannot be quickly and completely removed 

 like the solid normal pellets. Under such atmospheric 

 conditions we find as a rule a great number of soiled bags 

 which either are empty, having been abandoned by their 

 inhabitant, or contain a flaccid, diseased larva; or (b) the 

 drops of water cai-ried in by the larva when retreating into 

 its bag after feeding may increase the degree of moisture 

 inside the bag to an extent which affects the larva unfavourably. 



Whatever the primary cause, we find that under these condi- 

 tions the caterpillars behave abnormally. They turn around in 

 their bag, and such as are able to leave it through the opening 

 at the lower end start making a new bag. While engaged in 



