PA0HYTHELIA VILLOSELLA. 403 



following is a description made from a fairly typical, completed case 

 (really one of many) collected at Bournemouth by Mrs. and Master 

 Eric Cowl (to whose energy our knowledge of the life-history of this 

 species is very largely due) : As nearly as possible l'5in. in length 

 and -3in. wide. The posterior (unattached) end formed of a silken 

 tube -3in. in length (elongated to -6in. when spun down for pupa- 

 tion) . This being of soft texture naturally falls in and closes this end 

 of the case, but the larva backs itself readily out of it to get rid of its 

 excrement. The central tube is cylindrical, formed of white silk, and this 

 is covered with small pieces of grass, pine-needles, heather, stick, &c, 

 of varying length (average from •25in.- , 75in.), but all attached by the 

 basal end only, the other end free and pointing towards the posterior 

 end of the case. The pieces are intermixed with dead flowers of 

 Calluna, still arranged, however, as the sticks, and in the same regular 

 manner. The free open end, from which the larval head is protruded, 

 is much more developed dorsally, and forms a sort of hood that fits 

 close down to the surface on which the larva is crawling, when the 

 latter is disturbed and withdraws itself within the case. The cases 

 with the heather blossoms are much more bulky, especially towards the 

 anterior end, and as we have already noticed there is no trace of the 

 regular intermixture of leaves that characterises the case of C. nnicolor. 

 Wben full-fed the larva fixes down the anterior (mouth) of the case 

 with silk, turns round in it so that the head is towards the old 

 posterior end of the case and pupates in this position. [Described 

 June 2nd, 1899.] Two strange-looking cases (also sent by Mrs. Cowl 

 and collected at Bournemouth), which Chapman referred to this 

 species (about half -grown), were very peculiar, one was formed entirely 

 of very fine, light straws, sticking out at about 70° from the longitudinal 

 axis of the case, and hence very bristling in appearance, the other was 

 formed entirely of heather flowers, and as may be supposed was very 

 unlike normal cases of this species. Other cases made entirely of 

 small pieces of bracken frond, are exceedingly beautiful. Nickerl says 

 that the cases are constructed of different materials according to the 

 locality. In his own district in Bohemia, he says they are covered 

 longitudinally with short thick plant-stalks, whilst those found in the 

 Upper Engadine were mostly clothed with leaves of Vaccinium vitis- 

 idaea and hence they had a quite different appearance. Staudinger notes 

 that the cases he found at Constantinople were quite typical of the 

 species but smaller. Chapman observes that in Constant's collection are 

 some cases made of Vaccinium, others of leaves, some of grass, whilst 

 others from the New Forest are made of pine-needles. Mrs. Cowl 

 says that she observed cases in which pieces of charred stem had been 

 woven into the covering, these were found near where a fire had 

 occurred the preceding autumn. Hofmann says that the cases are 

 variable, especially those of the males, some of which are made of 

 thick grass or plant stems, others of round pieces of dead oak and 

 beech leaves ; the female cases are nearly always composed of plant 

 stalks placed lengthwise. Weir noted (August 14th, 1890) cases of 

 P. villusclla (containing living larvre) some made entirely of rush, some 

 with fragments of grass and heath, and one (the original case having 

 been taken away) with scraps of coloured paper. 



Habits of Larva. — Ova laid June 13th, female left case June 14th, 

 eggs hatched July 22nd, 1898,larva3 began to hybernate in October, when 



z2 



