1906.] 29 



tially brown-speckled) up to a deep fuscous dividing line, and dark brown beyond 

 it, but paler at the tornus ; this deep fuscous line appears to mark the actual 

 termen of the wing, but in reality the termen, which is often impossible to trace 

 from above though clearly visible from beneath, lies about -75 ram. inside this line. 

 Under-side silky brownish-grey, more brown towards the costa posteriorly, with the 

 dorsum broadly pale ochreous ; cilia grey-brown with an ill-defined darker line. 

 Alar, enp., 13-5— 17-5 mm. Hind-wings trapezoidal, very broad posteriorly with the 

 termen somewhat emarginate below the apex, satiny-grey ; cilia ochreous-grey. 

 Under-side concolorous with upper-side. Abdomen dorsally grey, with the first two 

 segments clothed with short hair-like golden-brown scales except along the anterior 

 margin, ventrally fuscous. The rather long ovipositor of the ? is often extruded 

 in dried specimens. 



The ground-colour of the fore-wings seems to be constant, but in some indi- 

 viduals the spots and the brown clouding (which varies somewhat in shade) are 

 much less well pronounced than in others. The fore-wings show a little variation 

 in the colour of the under-side, and much in expanse in both sexes, though the 

 females average larger than the males. 



Mr. Vine, who only found the moth in one restricted spot, tells 

 me that it is on the wing from about 7 to 8.30 p.m , during favour- 

 able weather, and that its flight is so slow and heavy that it has no 

 chance of escaping the net. In Stainton's " Tineina of Southern 

 Europe," it is given as occurring " in dry grassy places towards 

 evening," early in May (p. 58), and " on mountain-slopes and pasture- 

 fields " in May and June (p. 92). In the " Catalog " by Staudinger 

 and Eebel, M. silacellus is entered as an inhabitant of Central and 

 Southern Europe, Galicia, Livonia, Northern and Central Italy, 

 Dalmatia, and Bithynia. Unfortunately I have failed to find any 

 notes on its life-history, which appears to be entirely unknown ; we 

 must hope, however, that, through Mr. Vine's energy, it will be dis- 

 covered before long. 



The imago bears no resemblance to any other species in the 

 British List, although some of our earlier authors, including Haworth 

 and Stephens, erroneously applied Hiibner's name, whether as 

 " silacea " or " silacella,'' to Metzneria lappella, L., of which M. metz- 

 neriella was regarded by Ilaworth as a variety. 



It seems truly remarkable that the well-worked County of 

 Sussex should have yielded the three latest additions to our Lepi- 

 dopterous fauna, viz., Argyresthia illuminatella, Tortrioc pronubana, 

 and Mesophleps silacellus ! 



Norden, Corfe Castle : 



December I8th, 1905. 



