16 



IJune, 



Moulting Sickness. Larvoe of some species, even in confiueraent, appear 

 to experience but little difficulty in casting off their effete skins ; others, on the 

 contrary, and of these chiefly those of the Butterflies, Sphinges, Bomhyces, and 

 Pseudo-lomhyces, apparently naturally undergo a comparatively tedious and painful 

 process of ecdysis ; the appetite of the caterpillar thus affected leaves it, it fre- 

 quently seeks some retired spot, and having spun a fewer or greater number of 

 silken threads, attaches the hooks of the pro-legs thereto, and then, after the lapse 

 of a longer or shorter interval, bursts the now useless covering which invests it, and 

 makes its exit. During all this the larva should, as a rule, be left to its own re- 

 sources, but sometimes it may bo observed that it is incapable of freeing itself, in 

 which case assistance must be rendered before prostration takes place, by slitting 

 the old skin with a couple of needles carefully manipulated, cutting, by very fine 

 pointed scissors, the skin round any scab which may have been formed over a 

 wound, and pegging down the skin in cases where the pro-legs may have become 

 detached from the transverse silken threads, assisting meanwhile the operation by 

 moisture and warmth. It is very important to discriminate between the above 

 sickness and cases of starvation, since the treatment I'equired in the latter case is 

 necessarily converse of the above, and a conclusion respecting this may safely be 

 arrived at by attention to the following : — In the starved larva the capital segment 

 is comparatively of hydrocephalic proportions — it is, in the moulting larva, very- 

 small, the skin is plump and tense in the latter, while that of the former hangs 

 loosely ; the silken transverse threads too are absent in the victim of starvation, 

 which also exhibits a restless desperation in searching for food to appease its hun- 

 ger, sometimes snapping at pieces of frass and other substances, and as hastily 

 casting them aside, the moulting larva, on the other hand, remains stationary. 



DiarrllOD^. This is generally caused by improper feeding with too juicy or 

 too relaxing food ; in such cases, dry stunted foliage gathered from bleak exposed 

 situations, mature leaves, astringents, such as dark-coloured oak leaves, madder, &c., 

 should be tried with such larvae as will partake of them, or the food may be sprinkled 

 with powdered madder, chalk, &c. The converse of this complaint requires to be 

 treated with the young, juicy, immature leaves of the food-plant, and, in certain 

 cases, mostly among the Noctuce, the administration of lettuce and other natural 

 purgatives will have a salutary effect. 



Fungus. This is particularly apt to attack haiiy larvas, especially such as 

 hybernate, the subject — having doubtless first become unhealthy from confinement 

 in a damp, ill-ventilated atmosphere — is attacked by a species of didivm, after 

 which it is generally " all up," I do not know how far the use of hyposulphurous 

 acid or the hyposulphites might be applicable, but their effect might be tried. The 

 natural preventive is, doubtless, exposure to the sun's rays, and most collectors 

 must have noticed that the hybernating larvae of Arctia, Spilosoona, and others, take 

 every opportunity of sunning themselves, as if for the purpose of drying their 

 coats ; when there is no sun visible, currents of dry air will, probably, be the best 

 remedy. 



Soils, &c., for the use of Larvae about to change to Pupse. 



Considerable diversity of opinion, respecting the substances, mixtures, &c., 

 best adapted for this purpose, exists among Entomologists — probably at one time 



