COCCID^. 



321 



pear-shaped (pyriform) and white, witli exuvi;e at the anterior 

 extremity. Under a pocket lens the two larval moults may be 

 distinctly recognised. The male puparium is elongate, and composed 

 almost entirely of a pure white secretion, with the yellowish larval 

 moult at the anterior extremity. 



Chionaspis salicis (Linn.) 



The scales of this species are very common on ash, willow, and 

 other trees. In some parts of the country, notably in mid-(Jheshire, 

 we find young ash-trees from six to eighteen years 

 of age, and osiers from four years and upwards, 

 completely covered with these scales. They are 

 comparatively small, and if accurately measured 

 would probably be about 

 •75 mm. in length. 



A cursory examination 

 shows that two forms of 

 scale appear on the stems 

 —the male form (fig. .301) 

 and the female form (fig. 

 302). Sometimes we find 

 both sexes on the same 

 tree, at other times only 

 females are found. In 

 those cases where the 

 male form preponderates, 

 a whitish appearance is 

 presented, as in fig. 301, 

 where the male scales, or 

 puparia as they are called, entirely cover the bark of the young stem. 

 Those two forms, as seen collectively by the naked eye in figs. 301 

 and 302, and individually magnified in fig. 303 (7 and 3), represent 

 the male and female forms of Chionaspis salicis. 



If we lift a perfect female scale any time during the winter 

 months, turn it over, and examine the under side with a lens, or as 

 an opaque object with an inch objective, a considerable number of 

 beautiful red eggs will be noticed (fig. 303 (4)). In my younger days, 

 when working in the woods, I have often rubbed my thumb-nail 



X 



Female scales 

 of Chionaspis salicis 



0)1 stem of a five-year- 

 old balsam poiilai-. 



