68 
Y. NIISIMA. 
BLAN T DFORD n described as an ill-developed form of Scolytus esuriens BLFD. 
Twenty five specimens of this form have been collected by me ; and they 
were all found in the same trees together with that of Scolytus esuriens 
Blfd. In the course of my study I hope to be able to clear up such 
unsettled and doubtful cases. 
I express here my sincere gratitude to Prof. S. MatsüMURA, for giving 
me many valuable European specimens of Scolytidae. Also I am indebted 
for gifts of interesting specimens to Messrs Y. Nawa, M. Isiiida anti N. 
Mitsuhasiii. 
Scolytus esuriens Blandford. 
London, Trans. Ent. Soc., 1894, p. 77. 
Plate II. fig. 1-3. 
Food plant. Ulmus cctvipestris Sm. 
Distribution. Hokkaido : the Junsai-numa (BLANDFORD) ; Sapporo 
and Kotoni (NlISIMA). 
Scolytus esuriens Blfd. is a common species in Hokkaido and is very 
variable in size and colour. The females are generally larger than the 
males ; out of my seventy six specimens, the size of the females varies from 
4.5 to 6.5 mm. and that of the males. from 3.8 to 4.5 mm. The colour of 
elytra is black, with sides and apex more or less reddish, the reddish shade 
differing very much according to the specimens. Eight of the specimens 
which I have collected in the bark of an elm tree at Sapporo have very 
clearly edged elytra of reddish colour at the base, side and apex, and are 
nearly allied with the specimens of Scolytus Geoffroyi Goetze from Europe 
in their shade. Nearly all other specimens have the black elytra, with a 
slight reddish tinge at the side and apex. In very few specimens, the 
elytra is entirely reddish. 
It is a distinguishing character of Scolytus esuriens Blfd. that the 
males have three compressed hairs at the extremities of the last abdominal 
segment (Fig. 2) ; but not so in the females (Fig. 3). 
This species attacks the bark of the dead elm. I have collected many 
specimens in the firewood of elm, chiefly of large trunks ; but once I found 
1) London, Trans. Ent. Soc. j 8 <) 4 , p. 78 . 
