164 BEITISH LEPIDOPTERA. 



any other group of equal size, included in the so-called Micro- 

 Lepidoptera. 



Besides the large genus Nepticula, at least two other genera belong 

 to this superfamily, viz., 1'rifurcula and Scoliaula (Ijo/iemannia). 

 When more is known of the early stages of other genera, probably also 

 these, too, will have to be admitted. 



The impedimenta required for collecting the mines of these species 

 consist only of a small pocket lens, and a few tin boxes in which to 

 carry the leaves containing the mines when found. The specimens in 

 collections are almost all bred from mines thus obtained. The species 

 are mostly double- or continuously-brooded, and the mines may, there- 

 fore, be collected in the summer months, although autumn is the time 

 of year usually occupied with this pursuit. The whole existence of 

 one of these mining larvae is almost always spent within the confines 

 of a single leaf, and hence the area of study is, so to speak, circum- 

 scribed within these narrow limits. There are various means 

 of determining, in the larval state, all our British species. The points 

 which aid in this determination are : (1) The food-plant. (2) The 

 position of the egg. (3) The form of the mine. (4) The arrangement 

 of the frass. (5) The structural characters of the larva. 



The food-plants of almost all our British species are well-known. 

 The Bosaceae, Salicineae and the Cupuliferae supply, between them, the 

 food-plants of about five-sixths of the British species. The birch supports 

 at least 8 (? 9) species, the oak 5, hawthorn 6, and apple 5, 5 feed on rose, 

 6 on brambles, at least 3 (? 4) on the willows, and 4 on pear. The 

 Vacciniaceae support 2 species, the Urticaceae (elms) 3, whilst 6 

 other natural orders (including the Leyuminosae and Labiatae) contain 

 but one species of plant each, which is known to be acceptable to the 

 Nepticulid larvre, and each of these is tenanted by only a single species ; 

 the single Hypericum, species, however, is not so particular in its choice of 

 a single species for food-plant. The total number of the British species 

 (including doubtful ones) obtained from the Bosaceae and Cupuliferae 

 amounts to 58, whilst only 20 are obtained from plants of all other 

 natural orders. Many species are confined to a single food-plant, but 

 others are not so limited. Both the nut species, N. floslactella and N. 

 microtheriella, are also found on Carpinus betulus. N. aeneofasciella feeds 

 on Potentilla tormeniilla and Ayrimonia eupatoria ; N. oxyacanthella 

 occurs on apple and pear, as well as on mountain-ash, Cotoneaster affinis 

 and hawthorn ; N. atricollis on apple and hawthorn, as well as on pear; 

 N. anyulifasciella on Poterium sanyuisorba as well as rose ; whilst 

 Wood gives the palm, in this respect, to TV. aurella, which, he says, 

 feeds on bramble, strawberry, agrimony and Spiraea. He also considers 

 that N. yei, from Geum, is only a form of this species. 



Whether the palm should not be given to N. oxyacanthella is doubtful. 

 Fletcher says that he has never found N. aurella in the leaves of any- 

 thing but evergreen bramble (Bubus fruticosus), and he suspects that 

 the larvre on strawberry, agrimony, Sjriraea and Geum are N. yei, 

 which he has found in leaves of all these plants. As to N. aurella and A r . 

 yei being different species, Fletcher writes : " N. aurella and N. yei are 

 very much alike, still I can always breed them pure. The mines are 

 somewhat different, and the larvre occur at different seasons." He also 

 notes : " N. splendidissimella is quite distinct ; the mine is more distorted, 

 tends to be more in the outer angle of the leaf, and has a less tendency to 



