258 Dr. APzerius’s Obfervations on the Genus Paufus. 
It is not very uncommon in our days to fee ater and niger, piceus 
and fufcus, ufed promifcuoufly: but it was not fo originally with 
Linné; for, by ater he meant a colour of the blackeft kind; by miger, 
another of black and brown mixed togethers and by frceus, ftill ano- 
ther of a lighter caft, or with a greater portion of brown. “As to 
Sifeus, it was a dark colour, compofed of a mixture of black, brown, _ 
and cinereous. Having once afked him the difference between ater 
and mfger, I received this explanation from himfelf. It muft there- 
fore be genuine; and if we apply it to the prefent cafe, we fhall find. 
it agree admirably well, -for the colour of P. microcephalus is a dark 
brown, but underneath and on the forepart borderig on blackith ;. 
and of courfe Thunberg has approached very near the truth in 
calling it ziger, though I would rather give it the name of Aiceus. | 
Fabricius, in pointing out the fpecific difference of this infect, and 
{peaking particularly of its antenne, fays that their clava is irre 
guiaris. This word not being otherwife defined, it muft here be 
taken in the fenfe in which it is commonly ufed, and then it conveys. 
the idea of the clava being of a fhape either not always uniform, or 
deviating from the ordinary rules of nature. But neither is the cafe, 
for all that I have feen have been quite alike, and an oblong {pheroid 
is not a very uncommon form to be met with in nature; P./phero-. 
cerus, both the Paw/fi of Thunberg, and Cerocoma ruficollis of Fabricius, 
having, befides fomething fimilar to it, the upper joint of their an- 
tenne differently fhaped from thofe of other infects. 
After thefe details of the hiftory of P. microcephalus, I fhall now 
ftate the chief differences between it and P. /pherocerus. 
It is of the fame length, but fomewhat broader acrofs the elytra, 
and of a much darker colour, being alfo very little fhining, 
The 
