Description of Lepidopterous L'lrvcc. 365 



ed over. I have been unable to detect upon them the sphiules found 

 upon the thoracic legs of many other caterpillars. 



The pro-legs are wanting, but in their stead is a curious, sac-like de- 

 velopment of the under surfece of the body, which can be protruded 

 at points where the pro-legs would be situated if present, and by means 

 of which, combined with an undulatory motion of the whole ventral 

 region, but notably so of the posterior two thirds, the insect glides 

 gracefully along any smooth body. Like the slug, their progress upon 

 dry and dusty surfices is very slow and soon stops. No slime or mu- 

 cus is exuded. I have bred the larvae of eight species of this group, 

 during the present season, and a remark as to how it w^as done may 

 not be out of place. We have among lepidopterous larvae certain ones 

 which are known as "general feeders ;" that is, they will eat the foliage 

 of a great many different plants. Notable among these is the whole 

 family of the Arctians, and scarcely less general, in this respect, is the 

 group under consideration. I have found the larva3 of Empretia 

 stimulea (Clemens) on the papaw, raspberry, cherry, basswood, and 

 Indian corn, during the present season. In confinement, it will 

 eat one of these plants, one day, and an entirely different one on 

 the next. If not disturbed, a leaf, which they once begin to eat, will 

 be entirely devoured, wdthout the insect's leaving it, except the 

 basal fourth of the midrib. They devour the leaf backwards and for- 

 wards, from side to side, at right angles to the axis, moving backward 

 as they eat, until the leaf is consumed, when they seek the nearest one, 

 creep to the apex, lap the "hood" over in the usual manner, and 

 begin auew\ They are very voracious, and never seem to rest between 

 meals like other caterpillars, but wnll always be seen gnawing the leaf 

 greedily, so that they devour as much food as other caterpillars many 

 times their size. 



I fed my specimens, under common tumblers, putting them on the 

 under side of the leaf, which is their natural position, and then slid 

 the leaves under the glass, one edge of which was kept slightly raised 

 for sake of ventilation. When full fed they leave the food plant, and 

 soon after eject a few drops of a viscid, watery looking fluid and shrink 

 to two thirdstheir previous size. When these changes were observed, 

 I placed them in a box, Avith bits of paper, or a few dry leaves, and 

 the cocoon, which is dense, brown and oval, was finished in a very few 

 hours. Indeed, in more than one case, an hour and a half or two 

 hours only was necessary, for the insect to finish its cocoon, so far as to 

 be completely hidden, I am positive as to the identity of but one of 

 the species of which the descriptions follow. The cocoons of the others 

 are now in my possession, in various numbers, except the second and 



