114 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 



spruce paling posts. E. mollis is, however, brown or pale 

 brown in colour, while E. nigrinus is dark brown or blactc. In 

 E. mollis the fifth to eighth antennal joints are about twice as 

 long as broad; in E. nigrinus these joints are short and as 

 broad as long. 



The black Ernobius is not a common beetle, but its larvae 

 may frequently be found in pine shoots in our northern forests, 

 in Deeside and Speyside especially. I have also found it at 

 Beaufort in the larval state. 



The larva is white, wrinkled and curved, and has a brown 

 head and jaws and three pairs of short thoracic legs. It occurs 

 in the pith of the pine shoots, tunnelling them as the adult 

 Myelophilus does, but it is also occasionally found in the bark 

 of the stems of standing pines, adopting a habitat like that 

 of its congener E. mollis. I have found it in such situations 

 in the Low Wood of Culbin, and recently, in company with 

 Mr J. W. Mackay, found the adult beetle on young self-sown 

 pines on Culbin sands. 



At first glance Ernobius nigrinus is not unlike Myelophilus in 

 appearance, but it may readily be recognised by its long 

 antennae, and especially by the last three joints of the antennae 

 which, as in all the Ernobius beetles, are very long. J. W. M. 



Spruce Aphis Attacks : A Word of Caution. 



While the recent prominence given to the Green Spruce Aphis, 

 Mvzaphis abietifia, Walk., as an important enemy of young Sitka 

 spruce plantations, is satisfactory from the forest hygiene point 

 of view, a word of caution is necessary against attributing all 

 cases of spruce defoliation to this insect, even where it occurs in 

 numbers. This aphis does occasionally cause serious injury in 

 spruce plantations, but it is by no means always the primary 

 cause of the trouble. Again and again in the writer's experience 

 other agents than aphis have been found causing browning or 

 defoUation in Sitka and Norway spruce areas. The root fungi 

 Fomes and Agaricus, are two of the common agents found in 

 supposed Myzaphis outbreaks, and it is possible that other more 

 insidious fungous diseases may be present in such cases. 



In all cases of Myzaphis trouble it is desirable, and in fact 

 essential, that soil and root conditions should be studied, and 



