THE 



BRITISH NATURALIST. 



NEW SERIES* 



CHIONASPIS FRAXINT. (THE ASH-BARK SCALE.) 



BY A. T. GILLANDERS. 



Amongst the many varieties ot insects directly or indirectly injurious 

 to our forest trees, none is more conspicuous, or more universally dis- 

 tributed, than the Ash-bark Scale (Chionaspis fraxini). It is generally 

 found on trees varying from six to twenty years of age. Perhaps no insect 

 pest appears more puzzling to the practical man than the "Scale" or 

 Coccid. 



The Coccidse or Scale-insects belong to the order Hemiptera, which is 

 divided into two sub-divisions, viz. : — (i) Hemiptera-Heteroptera, includ- 

 ing the bugs; and (2) Hemiptera-Homoptera, including crickets, 

 cuckoo-spits, plant lice (Aphides), leaf-hoppers (Psyllids), scale-insects 

 (Coccidae). 



The investigation of the Coccida?, or Scale-insects, is of comparatively 

 modern date, and therefore very little bibliography is found to assist the 

 inquiring student, that little being very difficult to procure. A very 

 able text book, a Manual on general Entomology, published within the 

 last decade, dismisses the group in a single paragraph. In the present 

 state of our knowledge it is difficult to state who may have been the first 

 to study Coccids on a systematic basis, but the celebrated French Ento- 



