22 BRITISH BUTTERFLIES. 



knowing, as we now do, of the presence of the special glands on the 7th 

 and 8th abdominal segments, we suspect these as the origin of the 

 matter excreted, and thus used by the larvae. Aitken and Davidson note 

 that the larval cell of Baoris bada is powdered inside, but make no 

 remark that the larva is so covered. The larva of Erionota thrax is also 

 similarly covered. Scudder further adds that, "in diminutive keeping 

 with this, the larva of the Nearctic Amblysczrtes vialis, which," of all 

 the skippers known to him, " has the most palpable coating of ex- 

 traneous matter, resembling the flocculent secretions of the Coccidae, 

 and which is renewed early after each moult, also lives a partially 

 open life, extending itself at full length along the grass blades outside 

 its nest for a considerable part of its later life. Exactly the same 

 habit is found, according to Fletcher, in Pamphila mandan (Cyclopides 

 palaemon var.)." The origin and value of this extraneous matter 

 deserves much more careful study. 



Of the feeding-habits of the Urbicolids of the Nearctic region, 

 Scudder says (Butts. New England, ii., p. 1548) : " On escaping from 

 the egg, the caterpillars nearly always devour the entire egg-shell 

 (excepting the base) before their feet touch any other than the shell 

 surface. The caterpillars live almost entirely in concealment within 

 the nests mentioned, rarely leaving them, but usually reaching out for 

 their food from this cylinder, and withdrawing at the slightest alarm ; 

 to aid them, the caterpillars, in their earliest stage, but never so far as 

 I have been able to see in any later one, are provided with long, 

 recurved hairs on the last abdominal segment, by which a securer 

 hold must be established within the very narrow nest. Moreover, 

 they rarely feed at any other time than at night, so that a sight of one 

 of these caterpillars, unless the nest is picked to pieces, is, indeed, a 

 rarity, and this is the more striking when we consider that the butter- 

 flies of this tribe form a significant proportion of our butterfly fauna." 

 The damage done by " skipper " larvae is occasionally noted, e.g., Harris 

 observes that the larvae of the Nearctic Epargyreus tityrus sometimes 

 almost completely strips the leaves from the viscid-locust tree, whilst 

 Scudder observes (Butts. New Engl., p. 1391) that the larvae of Eudamus 

 proteus sometimes do damage in Florida to the crops of beans, etc. 

 We have already noted (antea, p. 9) that the larvae of Hidari irava 

 sometimes does damage to the foliage of the cocoa-nut palms in Sumatra, 

 where also the larvae of Erionota thrax occasionally ravage the plantains. 

 Except to say that, as a rule, the larvae confine themselves to the 

 immediate neighbourhood of their nests, and rarely wander, there 

 appears to have been enough already noted indirectly to give a fair 

 idea of the feeding-habits of the "skipper" larvae. 



The nocturnal feeding-habit of the Urbicolid larvae must also be of 

 considerable protective value, and, when to this is added the fact that 

 some larvae never leave their shelters even for food, but devour only 

 what they can reach from the entrance to their hiding-place, it must 

 be conceded that their resting- and feeding-habits must give a maxi- 

 mum of safety. Thus Aitken records that the larva of the Indian 

 Suastusyremius,B ever leaves the cell it makes, but feeds on the edges 

 or outer portions of it, whilst similar remarks arc made of Parnara 

 bevani; the larva of ( 'aprona ransonnetii remains within its hiding-place, 

 resting on the roof of the cell, and eats holes in the other portions of 

 the covering until a new one is needed. He also notes that the larva 



