1899-1900.] Dr R Stewart MacDougall on Genus Pissodes. 323 
Determination of the Species. 
The accompanying table is, with slight modifications (I have 
added scabricollis), that of Professor bfitsche (2). 
Posterior corners of 
prothorax right-angled 
or projecting somewhat 
sharply. The upper 
surface of the prothorax ' 
wrinkled and covered 
with a number of closely - 
arranged punctures. 
Wing covers with a 
narrow transverse band 
behind their middle. 
P. pini. 
Wing covers with a 
broad transverse band - 
behind their middle. 
Wing covers have 
longitudinal rows of 
large dots varying in 
size. 
P. piceoe . 
Wing covers with 
longitudinal rows of 
equally-sized dots. 
P. notatus. 
Beetles black. 
P. harcynice. 
Posterior corners of 
prothorax rounded and 
the deep punctures not 
so close together. 
Beetles rusty brown. 
P. piniphilus. 
Beetles with a more or less prominent raised 
middle line on the prothorax. Generally much 
smaller than harcyniae and not so black. 
P. scabricollis. 
In the Continental literature on the Pissodes, another form is 
mentioned — viz., P. validirodris , which was said to breed in pine 
cones. I have proved, however, that P. notatus and P. vali- 
dirostris are one and the same (3). 
A glance over the above table will show that the species 
resemble each other closely. This resemblance is close, in size, 
and colour, and round of life. Besides, the characteristic spots 
and bands (these latter formed from the coalescence of individual 
scales), so helpful in the determination of fresh specimens, get 
rubbed off in course of time, making the recognition of isolated 
not-fresh specimens troublesome. 
Size and colour of species also fluctuate within limits. For 
example, while a normal-sized P picece is not to be confused with 
a normal-sized P. notatus , I have taken specimens of piceae as 
small as an ordinary notatus, and not to be distinguished from the 
latter save by their different food plant. 
In the forest one may meet with plants and trees that have 
