112 LECANIT7M 



guarantees tlie synonyms set forth. In the majority 

 of instances the earlier writers have formed their 

 diagnoses from much too limited a series, often from a 

 single specimen, which has led to endless confusion. 



I do not propose here to enter into the details of the 

 synonymy ; much of this has already been set forth by 

 Mr. Douglas (1. c.), and I have little doubt, had that 

 author had the opportunity of examining and studying 

 the materials personally, he would have arrived at a 

 similar, if not identical, conclusion as myself. 



Habitat. On * hawthorn (Cratasgus oxyacantJia), 

 2 apple (Pyrus mains), 3 Cotoneaster spp., 4 elm (Ulmus 

 campestris), 5 sycamore (Acer pseudo-platanus), 6 oak 

 (Quercus robur), 7 alder (Alnus glutinosa), 8 willow (Salix 

 spp.), 9 rose, cultivated and wild (Rosa spp.), 10 hazel 

 (Gory his avellana), n lime (Tilia spp.), 12 horse-chestnut 

 (JEsculus spp.), 13 laurel (Prunus lauro-cerasus), 14 cherry, 

 15 plum, 16 wild sloe (Prunus spp.), and ll Euonymus sp. 

 It occurs freely on Nos. 1, 2, 4, 5, 6, 7, 11, 12, and 

 13 ; but has been found less freely on 3, 8, 9, 10, 14, 

 15, 16, and 17. 



It is abundant and generally distributed in suitable 

 localities throughout England, but is apparently very 

 local in Scotland and Wales. I have no Irish records. 



Distribution. Apparently very common in Europe. 

 Dr. Keh* gives as food-plants JSTos. 1, 2, 7, 12, and 

 15 of my list, and alsot Pyrus communis and Prunus 

 armeniaca. It is also recorded from North America 

 (King), where it has probably been introduced. 



EXPLANATION OF THE PLATE. 



PL LIV, fig. 1 . Adult females at period of parturition, 

 natural size in situ on branch of hawthorn (from 

 life). 



* ' Jahrbuch der Hamb. Wissench. Anstalten/ xviii, p. 228 (1900). 

 f I have found quite recently a pear tree in the neighbourhood of Chester 

 badly infested with this coccid. 



