288 BRITISH LEPIDOPTERA. 



of bark and minute pieces of vegetable debris (apparently rarely 

 grass) placed irregularly, the particles really small (but large compared 

 with those used by the larva of Luffia lapidella) and there is silk spun 

 over the outside. The case has a particularly blackish appearance 

 (Described May 27th, 1899, from cases found on tree-trunks by 

 Whittle, at Eastwood). Chapman describes a case as 9'4mm. in 

 extreme length, covered with black dead vegetable matter — dried 

 scraps of bark, oak-leaves, &c. — with some loose spinning outside it, 

 and some coloration due to green lichen. Another has pieces of dried 

 grass, scraps of oak-bracts, &c. (Described June 18th, 1899, from 

 cases taken by Prout at Chingford). Zeller notices the case as taper- 

 ing conically behind, and, instead of being covered with grass stems (as 

 that of F. nitidella), it is covered with rounded particles of white birch- 

 bark, and other leaf -like substances. He adds that " one might 

 suspect that the larvae used these materials because grass-stems were 

 not available," but that " when provided with grass they did not use 

 it, and when there was insufficient birch-bark they stole the material 

 from other cases." [Bruand says that the case resembles that 

 of P. salicolella, i.e., it is covered with particles of wood and little 

 pieces of bark."] Herrich-Schaffer's figures (Neue Schmett., figs. 11-12) 

 of this case show it as larger, more slender, and with more material 

 fastened outside than that of B. sepium. The male pupa-case is 

 figured as having emerged to about the 6th abdominal segment. 

 Mitford describes the cases as having " the materials placed crosswise, 

 and with no lengthy pieces of grass or straw used in their formation." 

 Two of Mitford's cases (in Dr. Mason's collection) are large, with 

 materials standing well off the case. The male case is 6-25mm. long, 

 very dark, and among other things has a very definite piece of brown 

 leaf fastened to it, also at the attached end the exuviated larval skin, 

 but this apparently results from tearing the case in removing it from 

 its attachments. The female case is 10mm. long, brown, with scraps 

 of dead leaf, and Avide from the projection of many of the scraps. 

 Chapman states that a male case from Eastwood has the larval skin 

 wedged tightly into the spinning that has resulted from the removal of 

 the case from its attachment. He also notes that the cases in Con- 

 stant's collection appear to have a few bits of grass on them. The 

 smallest of several cases, obtained November 1899, measured 2mm. in 

 length, and was covered with very minute fragments ; one, about 4mm. 

 long, has two relatively large flat pieces of bark laid flatly against it on 

 one side, and a large piece (3mm. long) on the other, with smaller 

 portions ; a larger case (5mm. long) has various pieces of dark brownish 

 bark, and one piece looks like the pale brown scale of a leafbud. The 

 larvae in these cases do not carry themselves at all erect, except at 

 times when gravity assists, usually dragging the cases along fairly 

 flatly. 



Comparison of cases of Proutia betulina, Luffia lapidella, and 

 Bacotia sepium. — Small cases of P. betulina, 2mm. long (obtained at 

 Eastwood, in November, 1899), show definite Luffiid affinities. These 

 are carried in a very upright manner, not so absolutely so, as B. sepium 

 larva carries its case, but very nearly as much so as Luffia lapidella. 

 It further resembles the case of L. lapidella in having a very slight but 

 recognisable curvature, one side being straight (tbe lower one as the 

 case is carried), the other, or forward one, being curved. The materials 



