NEPTICTOA OXYACANTHELLA. 203 



menhangenden Kothreihe erftillt, die nur gegen den Ausgang der 

 Mine bin verfeinerfc aufhort. An der Ausgangsofmung ist der Quer- 

 durchmesser des Ganges etwa 1 '"." 



LARVA. Length 2 lines ; bright green, the dorsal vessel darker, 

 head green, with a faint brownish tinge, the mouth, and two lines 

 receding from it, light brown (Stainton). The head of the larva is 

 dark (usually dark grey or black), and is always conspicuous in the 

 mine. The ground-colour of the larva is green, of a rather less bluish 

 tint than that of the larva of X. yratiosella, and the cephalic ganglia 

 are just visible behind the head (of these there is no trace in the larva 

 of N. gratioRella). The intestinal canal is yellowish, and by this the 

 larva can at once be separated from that of N. pijri. Frey writes : 

 "Die Raupe ist, etwa 2'" messend, lebhaft grasgriin mit dunkel 

 hindurchschimmerndem Darmkanale. Der Kopf zeigt sich braunlich, 

 die Mundtheile braun." The larva mines with its dorsurn uppermost 

 in the mine. 



COMPARISON OF THE MINES AND LARVA OF N. OXYACANTHELLA WITH 

 THOSE OF N. PYRI AND N. MiNuscuLELLA. These three species make 

 gallery mines in the pear. X. oxyacemtltetla and X. pyri make narrow 

 galleries with the coil arrangement, X. minusctdella a wide gallery 

 with the frass collected into the middle. All have bright green larvae ; 

 A T . o.ri/acantkella and X. minitxcidella lie on the underside, N. pyi'i 

 on either the upper or underside, but with a very decided pre- 

 ference for the former, and I am inclined to think that it is the foul- 

 ing of the upper surface with honey-dew that generally drives it to 

 the lower one. X T . oxyacantlu'lla can be recognised by its long and 

 bold mine, by the dark head of the larva with the cephalic ganglia just 

 visible behind, and by the yellowish intestinal canal the characters, 

 in fact, that distinguish it when feeding in hawthorn leaves. The 

 mines of the other two are small and cramped ; the larva) have pale 

 heads, and no trace of the cephalic ganglia, a tinge of blue in their 

 ground colour, and the hinder part of the intestinal canal in 

 N. pyri red. Seldom can any hesitation be felt in distinguishing 

 X. o.ryacanthella from X T . pyri, and still less from X. minusadclla 

 (Wood). 



COCOON. -The cocoon is oval, dull greenish-brown, inclining to 

 yellowish-brown at the wider end, through which the pupa protrudes 

 its anterior segments previously to the emergence of the imago 

 (Stainton). Hind calls the colour of the cocoon " purplish-brown." 

 It is usually spun on the surface of the ground, and is smooth and 

 dark brown in colour (Wood). Frey writes : " Der Cocon ist braun, 

 ziemlich regelmassig und langlich rund." 



FOOD-PLANTS. Crataeyw oxyacantlta, Pyms mains, P. communis, P. 

 aucuparia and Cotoneaster affinis (Fletcher). 



TIME OF APPEARANCE. The imago appears in May and August, 

 from larvae collected in September-October and July respectively. The 

 insect is distinctly stated by Wood to be single-brooded, the larva to be 

 found only in September and October at Hereford, the imago 

 appearing in June. Bower records mines found October 3rd, 1891, at 

 Lewisham, on hawthorn, and on October 3rd, 1892, at Mottingham, 

 on apple. Stainton took the imago at Dartford Heath, on June 22nd, 

 1852, and from pupae kept in confinement bred imagines on June 23rd, 

 1852, March 12th, 23rd, May 3rd, 5th, 1853, April 6th and 9th, and 



