NEPTICULA BASALELLA. 301 



excrement, which is now greenish-grey, does not occupy the whole 

 width of the mine, but leaves a considerable space on either side ; in 

 the progress of the larva in its mine (generally towards the edge of 

 leaf), it crosses several of the side ribs of the leaf. When full-fed, the 

 larva leaves the mine to spin its cocoon (Stainton). Wood notes that 

 " in the first part of the mine there is the usual concretionary arrange- 

 ment of frass (embracing first two larval skins), the second portion 

 is characterised by unmistakeable coiling ; in the third part the coiling 

 is gone, and the frass is scattered irregularly. (The coiling in the 

 second portion is the best means of distinguishing the mine of this 

 species from that of N. turicella, which never has the slightest indica- 

 tion of it.)" Sorhagen notes the mine as very fine at the commence- 

 ment, much broader later ; the frass-line at first brownish and filling 

 the gallery, later greenish-grey, placed along the centre of the mine, 

 which now has pale margins. 



Larva. — The head is pale brown, the cephalic ganglia and ventral 

 cord invisible (Wood). Length 21 lines ; pale greenish-white in 

 colour ; dorsal vessel greenish-brown ; head pale brownish ; mouth 

 and margins of head reddish-brown (Stainton). 



Cocoon. — The cocoons average 2 mm. in length and 1*3 mm. in 

 width. It is of a much yellower colour than that of N. turicella ; 

 oval in outline and not very much flattened. The silk is arranged 

 transversely, loosely, and has a somewhat coarse appearance. The 

 cocoon proper is enveloped in a mass of loose flossy silk of the same 

 colour as the cocoon, this outer covering, however, is much less thick 

 than that covering the cocoon of N. turicella. Compared with the 

 latter the cocoon of N. bazalella is rather less in size, more orange in 

 tint, made of coarser silk, and with a much thinner outer covering. 

 [Described June 7th, 1898, from cocoons sent by Dr. Wood.] The 

 cocoon is oblong-oval in shape, pale yellow in colour, and rather 

 flossy. The pupa protrudes its anterior segments from the cocoon before 

 the emergence of the imago (Stainton). Frey says that " the cocoon is 

 oval, very little flattened, pale ochreous-yellow in colour, and rough." 



Food-plant.— Fat/us sylvatica. 



Time of appearance. — This species is double-brooded, appearing 

 in May and August, the larva? of these broods feeding in October and 

 June- July respectively. Imagines were taken at Arnhem, by De Rooy, 

 on May 20th, 1873. Threlfall found larvae on October 13th, 1887, at 

 Ashton Park, which produced imagines the following April 10th, 

 onwards. Stainton found larvae at Box Hill, June 25th, 1861 ; he 

 bred imagines from Lewisham larvae April 14th-29th, 1853„ and 

 March 31st, April 1st, 8th, 12th, 14th, 28th, 1855. A specimen in 

 the Stainton collection was bred by Threlfall, at Preston, May 3rd, 

 1888. 



Localities. — Doubtful. — Devon: Dawlish (Stainton). Durham: Darling- 

 ton (Stainton). Edinburgh: Balerno (Logan). Gloucester : Bristol (Stainton). 

 Hereford : Tarrington (Wood). Kent : Lewisham (Stainton). Lancashire : Grange, 

 Ashton Park, nr. Preston (Threlfall), Manchester (Stainton). Norfolk: King's 

 Lynn, common (Atmore). Northumberland: Newcastle (Stainton). Perth: Mon- 

 creiffe Hill (Moncreirie). Surrey : Box Hill (Douglas), Mickleham (Stainton), 

 Haslemere (Barrett). Sussex: common — Abbott's Wood, Brighton, Worthing 

 (Fletcher). Westmorland: Windermere, Witherslack (Hodgkinson). 



Distribution. — Austria : Vienna (Metzner, teste Heinemann). 

 France: Crevant (Sand). Germany: generally distributed (Heine- 



